ALT-BU-2024-8739-1
Branch sisyphus update bulletin.
Package python3-module-asyncssh updated to version 2.14.2-alt1 for branch sisyphus in task 350401.
Closed vulnerabilities
BDU:2023-08853
Уязвимость реализации протокола SSH, связанная с возможностью откорректировать порядковые номера пакетов в процессе согласования соединения и добиться удаления произвольного числа служебных SSH-сообщений, позволяющая нарушителю обойти проверки целостности, отключить существующие функции безопасности, получить несанкционированный доступ к защищаемой информации
Modified: 2024-11-21
CVE-2023-46445
An issue in AsyncSSH before 2.14.1 allows attackers to control the extension info message (RFC 8308) via a man-in-the-middle attack, aka a "Rogue Extension Negotiation."
- http://packetstormsecurity.com/files/176280/Terrapin-SSH-Connection-Weakening.html
- http://packetstormsecurity.com/files/176280/Terrapin-SSH-Connection-Weakening.html
- https://github.com/advisories/GHSA-cfc2-wr2v-gxm5
- https://github.com/advisories/GHSA-cfc2-wr2v-gxm5
- https://github.com/ronf/asyncssh/blob/develop/docs/changes.rst
- https://github.com/ronf/asyncssh/blob/develop/docs/changes.rst
- https://github.com/ronf/asyncssh/security/advisories/GHSA-cfc2-wr2v-gxm5
- https://github.com/ronf/asyncssh/security/advisories/GHSA-cfc2-wr2v-gxm5
- FEDORA-2023-d2956318e4
- FEDORA-2023-d2956318e4
- https://security.netapp.com/advisory/ntap-20231222-0001/
- https://security.netapp.com/advisory/ntap-20231222-0001/
- https://www.terrapin-attack.com
- https://www.terrapin-attack.com
Modified: 2024-11-21
CVE-2023-46446
An issue in AsyncSSH before 2.14.1 allows attackers to control the remote end of an SSH client session via packet injection/removal and shell emulation, aka a "Rogue Session Attack."
- http://packetstormsecurity.com/files/176280/Terrapin-SSH-Connection-Weakening.html
- http://packetstormsecurity.com/files/176280/Terrapin-SSH-Connection-Weakening.html
- https://github.com/advisories/GHSA-c35q-ffpf-5qpm
- https://github.com/advisories/GHSA-c35q-ffpf-5qpm
- https://github.com/ronf/asyncssh/blob/develop/docs/changes.rst
- https://github.com/ronf/asyncssh/blob/develop/docs/changes.rst
- https://github.com/ronf/asyncssh/security/advisories/GHSA-c35q-ffpf-5qpm
- https://github.com/ronf/asyncssh/security/advisories/GHSA-c35q-ffpf-5qpm
- FEDORA-2023-d2956318e4
- FEDORA-2023-d2956318e4
- https://security.netapp.com/advisory/ntap-20231222-0001/
- https://security.netapp.com/advisory/ntap-20231222-0001/
- https://www.terrapin-attack.com
- https://www.terrapin-attack.com
Modified: 2024-12-02
CVE-2023-48795
The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity checks such that some packets are omitted (from the extension negotiation message), and a client and server may consequently end up with a connection for which some security features have been downgraded or disabled, aka a Terrapin attack. This occurs because the SSH Binary Packet Protocol (BPP), implemented by these extensions, mishandles the handshake phase and mishandles use of sequence numbers. For example, there is an effective attack against SSH's use of ChaCha20-Poly1305 (and CBC with Encrypt-then-MAC). The bypass occurs in chacha20-poly1305@openssh.com and (if CBC is used) the -etm@openssh.com MAC algorithms. This also affects Maverick Synergy Java SSH API before 3.1.0-SNAPSHOT, Dropbear through 2022.83, Ssh before 5.1.1 in Erlang/OTP, PuTTY before 0.80, AsyncSSH before 2.14.2, golang.org/x/crypto before 0.17.0, libssh before 0.10.6, libssh2 through 1.11.0, Thorn Tech SFTP Gateway before 3.4.6, Tera Term before 5.1, Paramiko before 3.4.0, jsch before 0.2.15, SFTPGo before 2.5.6, Netgate pfSense Plus through 23.09.1, Netgate pfSense CE through 2.7.2, HPN-SSH through 18.2.0, ProFTPD before 1.3.8b (and before 1.3.9rc2), ORYX CycloneSSH before 2.3.4, NetSarang XShell 7 before Build 0144, CrushFTP before 10.6.0, ConnectBot SSH library before 2.2.22, Apache MINA sshd through 2.11.0, sshj through 0.37.0, TinySSH through 20230101, trilead-ssh2 6401, LANCOM LCOS and LANconfig, FileZilla before 3.66.4, Nova before 11.8, PKIX-SSH before 14.4, SecureCRT before 9.4.3, Transmit5 before 5.10.4, Win32-OpenSSH before 9.5.0.0p1-Beta, WinSCP before 6.2.2, Bitvise SSH Server before 9.32, Bitvise SSH Client before 9.33, KiTTY through 0.76.1.13, the net-ssh gem 7.2.0 for Ruby, the mscdex ssh2 module before 1.15.0 for Node.js, the thrussh library before 0.35.1 for Rust, and the Russh crate before 0.40.2 for Rust.
- http://packetstormsecurity.com/files/176280/Terrapin-SSH-Connection-Weakening.html
- http://packetstormsecurity.com/files/176280/Terrapin-SSH-Connection-Weakening.html
- 20240313 APPLE-SA-03-07-2024-2 macOS Sonoma 14.4
- 20240313 APPLE-SA-03-07-2024-2 macOS Sonoma 14.4
- [oss-security] 20231218 CVE-2023-48795: Prefix Truncation Attacks in SSH Specification (Terrapin Attack)
- [oss-security] 20231218 CVE-2023-48795: Prefix Truncation Attacks in SSH Specification (Terrapin Attack)
- [oss-security] 20231219 Re: CVE-2023-48795: Prefix Truncation Attacks in SSH Specification (Terrapin Attack)
- [oss-security] 20231219 Re: CVE-2023-48795: Prefix Truncation Attacks in SSH Specification (Terrapin Attack)
- [oss-security] 20231220 Re: CVE-2023-48795: Prefix Truncation Attacks in SSH Specification (Terrapin Attack)
- [oss-security] 20231220 Re: CVE-2023-48795: Prefix Truncation Attacks in SSH Specification (Terrapin Attack)
- [oss-security] 20240306 Multiple vulnerabilities in Jenkins plugins
- [oss-security] 20240306 Multiple vulnerabilities in Jenkins plugins
- [oss-security] 20240417 Terrapin vulnerability in Jenkins CLI client
- [oss-security] 20240417 Terrapin vulnerability in Jenkins CLI client
- https://access.redhat.com/security/cve/cve-2023-48795
- https://access.redhat.com/security/cve/cve-2023-48795
- https://arstechnica.com/security/2023/12/hackers-can-break-ssh-channel-integrity-using-novel-data-corruption-attack/
- https://arstechnica.com/security/2023/12/hackers-can-break-ssh-channel-integrity-using-novel-data-corruption-attack/
- https://bugs.gentoo.org/920280
- https://bugs.gentoo.org/920280
- https://bugzilla.redhat.com/show_bug.cgi?id=2254210
- https://bugzilla.redhat.com/show_bug.cgi?id=2254210
- https://bugzilla.suse.com/show_bug.cgi?id=1217950
- https://bugzilla.suse.com/show_bug.cgi?id=1217950
- https://crates.io/crates/thrussh/versions
- https://crates.io/crates/thrussh/versions
- https://filezilla-project.org/versions.php
- https://filezilla-project.org/versions.php
- https://forum.netgate.com/topic/184941/terrapin-ssh-attack
- https://forum.netgate.com/topic/184941/terrapin-ssh-attack
- https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.10&id=10e09e273f69e149389b3e0e5d44b8c221c2e7f6
- https://git.libssh.org/projects/libssh.git/commit/?h=stable-0.10&id=10e09e273f69e149389b3e0e5d44b8c221c2e7f6
- https://github.com/advisories/GHSA-45x7-px36-x8w8
- https://github.com/advisories/GHSA-45x7-px36-x8w8
- https://github.com/apache/mina-sshd/issues/445
- https://github.com/apache/mina-sshd/issues/445
- https://github.com/connectbot/sshlib/commit/5c8b534f6e97db7ac0e0e579331213aa25c173ab
- https://github.com/connectbot/sshlib/commit/5c8b534f6e97db7ac0e0e579331213aa25c173ab
- https://github.com/connectbot/sshlib/compare/2.2.21...2.2.22
- https://github.com/connectbot/sshlib/compare/2.2.21...2.2.22
- https://github.com/cyd01/KiTTY/issues/520
- https://github.com/cyd01/KiTTY/issues/520
- https://github.com/drakkan/sftpgo/releases/tag/v2.5.6
- https://github.com/drakkan/sftpgo/releases/tag/v2.5.6
- https://github.com/erlang/otp/blob/d1b43dc0f1361d2ad67601169e90a7fc50bb0369/lib/ssh/doc/src/notes.xml#L39-L42
- https://github.com/erlang/otp/blob/d1b43dc0f1361d2ad67601169e90a7fc50bb0369/lib/ssh/doc/src/notes.xml#L39-L42
- https://github.com/erlang/otp/releases/tag/OTP-26.2.1
- https://github.com/erlang/otp/releases/tag/OTP-26.2.1
- https://github.com/golang/crypto/commit/9d2ee975ef9fe627bf0a6f01c1f69e8ef1d4f05d
- https://github.com/golang/crypto/commit/9d2ee975ef9fe627bf0a6f01c1f69e8ef1d4f05d
- https://github.com/hierynomus/sshj/issues/916
- https://github.com/hierynomus/sshj/issues/916
- https://github.com/janmojzis/tinyssh/issues/81
- https://github.com/janmojzis/tinyssh/issues/81
- https://github.com/jtesta/ssh-audit/commit/8e972c5e94b460379fe0c7d20209c16df81538a5
- https://github.com/jtesta/ssh-audit/commit/8e972c5e94b460379fe0c7d20209c16df81538a5
- https://github.com/libssh2/libssh2/pull/1291
- https://github.com/libssh2/libssh2/pull/1291
- https://github.com/mkj/dropbear/blob/17657c36cce6df7716d5ff151ec09a665382d5dd/CHANGES#L25
- https://github.com/mkj/dropbear/blob/17657c36cce6df7716d5ff151ec09a665382d5dd/CHANGES#L25
- https://github.com/mscdex/ssh2/commit/97b223f8891b96d6fc054df5ab1d5a1a545da2a3
- https://github.com/mscdex/ssh2/commit/97b223f8891b96d6fc054df5ab1d5a1a545da2a3
- https://github.com/mwiede/jsch/compare/jsch-0.2.14...jsch-0.2.15
- https://github.com/mwiede/jsch/compare/jsch-0.2.14...jsch-0.2.15
- https://github.com/mwiede/jsch/issues/457
- https://github.com/mwiede/jsch/issues/457
- https://github.com/mwiede/jsch/pull/461
- https://github.com/mwiede/jsch/pull/461
- https://github.com/net-ssh/net-ssh/blob/2e65064a52d73396bfc3806c9196fc8108f33cd8/CHANGES.txt#L14-L16
- https://github.com/net-ssh/net-ssh/blob/2e65064a52d73396bfc3806c9196fc8108f33cd8/CHANGES.txt#L14-L16
- https://github.com/NixOS/nixpkgs/pull/275249
- https://github.com/NixOS/nixpkgs/pull/275249
- https://github.com/openssh/openssh-portable/commits/master
- https://github.com/openssh/openssh-portable/commits/master
- https://github.com/paramiko/paramiko/issues/2337
- https://github.com/paramiko/paramiko/issues/2337
- https://github.com/PowerShell/Win32-OpenSSH/issues/2189
- https://github.com/PowerShell/Win32-OpenSSH/issues/2189
- https://github.com/PowerShell/Win32-OpenSSH/releases/tag/v9.5.0.0p1-Beta
- https://github.com/PowerShell/Win32-OpenSSH/releases/tag/v9.5.0.0p1-Beta
- https://github.com/proftpd/proftpd/blob/0a7ea9b0ba9fcdf368374a226370d08f10397d99/RELEASE_NOTES
- https://github.com/proftpd/proftpd/blob/0a7ea9b0ba9fcdf368374a226370d08f10397d99/RELEASE_NOTES
- https://github.com/proftpd/proftpd/blob/d21e7a2e47e9b38f709bec58e3fa711f759ad0e1/RELEASE_NOTES
- https://github.com/proftpd/proftpd/blob/d21e7a2e47e9b38f709bec58e3fa711f759ad0e1/RELEASE_NOTES
- https://github.com/proftpd/proftpd/blob/master/RELEASE_NOTES
- https://github.com/proftpd/proftpd/blob/master/RELEASE_NOTES
- https://github.com/proftpd/proftpd/issues/456
- https://github.com/proftpd/proftpd/issues/456
- https://github.com/rapier1/hpn-ssh/releases
- https://github.com/rapier1/hpn-ssh/releases
- https://github.com/ronf/asyncssh/blob/develop/docs/changes.rst
- https://github.com/ronf/asyncssh/blob/develop/docs/changes.rst
- https://github.com/ronf/asyncssh/tags
- https://github.com/ronf/asyncssh/tags
- https://github.com/ssh-mitm/ssh-mitm/issues/165
- https://github.com/ssh-mitm/ssh-mitm/issues/165
- https://github.com/TeraTermProject/teraterm/commit/7279fbd6ef4d0c8bdd6a90af4ada2899d786eec0
- https://github.com/TeraTermProject/teraterm/commit/7279fbd6ef4d0c8bdd6a90af4ada2899d786eec0
- https://github.com/TeraTermProject/teraterm/releases/tag/v5.1
- https://github.com/TeraTermProject/teraterm/releases/tag/v5.1
- https://github.com/warp-tech/russh/releases/tag/v0.40.2
- https://github.com/warp-tech/russh/releases/tag/v0.40.2
- https://gitlab.com/libssh/libssh-mirror/-/tags
- https://gitlab.com/libssh/libssh-mirror/-/tags
- https://groups.google.com/g/golang-announce/c/-n5WqVC18LQ
- https://groups.google.com/g/golang-announce/c/-n5WqVC18LQ
- https://groups.google.com/g/golang-announce/c/qA3XtxvMUyg
- https://groups.google.com/g/golang-announce/c/qA3XtxvMUyg
- https://help.panic.com/releasenotes/transmit5/
- https://help.panic.com/releasenotes/transmit5/
- https://jadaptive.com/important-java-ssh-security-update-new-ssh-vulnerability-discovered-cve-2023-48795/
- https://jadaptive.com/important-java-ssh-security-update-new-ssh-vulnerability-discovered-cve-2023-48795/
- [debian-lts-announce] 20231226 [SECURITY] [DLA 3694-1] openssh security update
- [debian-lts-announce] 20231226 [SECURITY] [DLA 3694-1] openssh security update
- [debian-lts-announce] 20240125 [SECURITY] [DLA 3718-1] php-phpseclib security update
- [debian-lts-announce] 20240125 [SECURITY] [DLA 3718-1] php-phpseclib security update
- [debian-lts-announce] 20240125 [SECURITY] [DLA 3719-1] phpseclib security update
- [debian-lts-announce] 20240125 [SECURITY] [DLA 3719-1] phpseclib security update
- [debian-lts-announce] 20240425 [SECURITY] [DLA 3794-1] putty security update
- [debian-lts-announce] 20240425 [SECURITY] [DLA 3794-1] putty security update
- FEDORA-2024-39a8c72ea9
- FEDORA-2024-39a8c72ea9
- FEDORA-2024-3bb23c77f3
- FEDORA-2024-3bb23c77f3
- FEDORA-2024-3fd1bc9276
- FEDORA-2024-3fd1bc9276
- FEDORA-2023-20feb865d8
- FEDORA-2023-20feb865d8
- FEDORA-2024-06ebb70bdd
- FEDORA-2024-06ebb70bdd
- FEDORA-2023-e77300e4b5
- FEDORA-2023-e77300e4b5
- FEDORA-2024-71c2c6526c
- FEDORA-2024-71c2c6526c
- FEDORA-2024-d946b9ad25
- FEDORA-2024-d946b9ad25
- FEDORA-2024-ae653fb07b
- FEDORA-2024-ae653fb07b
- FEDORA-2023-cb8c606fbb
- FEDORA-2023-cb8c606fbb
- FEDORA-2024-7b08207cdb
- FEDORA-2024-7b08207cdb
- FEDORA-2024-2705241461
- FEDORA-2024-2705241461
- FEDORA-2024-fb32950d11
- FEDORA-2024-fb32950d11
- FEDORA-2023-153404713b
- FEDORA-2023-153404713b
- FEDORA-2024-a53b24023d
- FEDORA-2024-a53b24023d
- FEDORA-2023-55800423a8
- FEDORA-2023-55800423a8
- FEDORA-2023-0733306be9
- FEDORA-2023-0733306be9
- FEDORA-2023-b87ec6cf47
- FEDORA-2023-b87ec6cf47
- https://matt.ucc.asn.au/dropbear/CHANGES
- https://matt.ucc.asn.au/dropbear/CHANGES
- https://nest.pijul.com/pijul/thrussh/changes/D6H7OWTTMHHX6BTB3B6MNBOBX2L66CBL4LGSEUSAI2MCRCJDQFRQC
- https://nest.pijul.com/pijul/thrussh/changes/D6H7OWTTMHHX6BTB3B6MNBOBX2L66CBL4LGSEUSAI2MCRCJDQFRQC
- https://news.ycombinator.com/item?id=38684904
- https://news.ycombinator.com/item?id=38684904
- https://news.ycombinator.com/item?id=38685286
- https://news.ycombinator.com/item?id=38685286
- https://news.ycombinator.com/item?id=38732005
- https://news.ycombinator.com/item?id=38732005
- https://nova.app/releases/#v11.8
- https://nova.app/releases/#v11.8
- https://oryx-embedded.com/download/#changelog
- https://oryx-embedded.com/download/#changelog
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2024-0002
- https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2024-0002
- https://roumenpetrov.info/secsh/#news20231220
- https://roumenpetrov.info/secsh/#news20231220
- GLSA-202312-16
- GLSA-202312-16
- GLSA-202312-17
- GLSA-202312-17
- https://security.netapp.com/advisory/ntap-20240105-0004/
- https://security.netapp.com/advisory/ntap-20240105-0004/
- https://security-tracker.debian.org/tracker/CVE-2023-48795
- https://security-tracker.debian.org/tracker/CVE-2023-48795
- https://security-tracker.debian.org/tracker/source-package/libssh2
- https://security-tracker.debian.org/tracker/source-package/libssh2
- https://security-tracker.debian.org/tracker/source-package/proftpd-dfsg
- https://security-tracker.debian.org/tracker/source-package/proftpd-dfsg
- https://security-tracker.debian.org/tracker/source-package/trilead-ssh2
- https://security-tracker.debian.org/tracker/source-package/trilead-ssh2
- https://support.apple.com/kb/HT214084
- https://support.apple.com/kb/HT214084
- https://thorntech.com/cve-2023-48795-and-sftp-gateway/
- https://thorntech.com/cve-2023-48795-and-sftp-gateway/
- https://twitter.com/TrueSkrillor/status/1736774389725565005
- https://twitter.com/TrueSkrillor/status/1736774389725565005
- https://ubuntu.com/security/CVE-2023-48795
- https://ubuntu.com/security/CVE-2023-48795
- https://winscp.net/eng/docs/history#6.2.2
- https://winscp.net/eng/docs/history#6.2.2
- https://www.bitvise.com/ssh-client-version-history#933
- https://www.bitvise.com/ssh-client-version-history#933
- https://www.bitvise.com/ssh-server-version-history
- https://www.bitvise.com/ssh-server-version-history
- https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html
- https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html
- https://www.crushftp.com/crush10wiki/Wiki.jsp?page=Update
- https://www.crushftp.com/crush10wiki/Wiki.jsp?page=Update
- DSA-5586
- DSA-5586
- DSA-5588
- DSA-5588
- https://www.freebsd.org/security/advisories/FreeBSD-SA-23:19.openssh.asc
- https://www.freebsd.org/security/advisories/FreeBSD-SA-23:19.openssh.asc
- https://www.lancom-systems.de/service-support/allgemeine-sicherheitshinweise#c243508
- https://www.lancom-systems.de/service-support/allgemeine-sicherheitshinweise#c243508
- https://www.netsarang.com/en/xshell-update-history/
- https://www.netsarang.com/en/xshell-update-history/
- https://www.openssh.com/openbsd.html
- https://www.openssh.com/openbsd.html
- https://www.openssh.com/txt/release-9.6
- https://www.openssh.com/txt/release-9.6
- https://www.openwall.com/lists/oss-security/2023/12/18/2
- https://www.openwall.com/lists/oss-security/2023/12/18/2
- https://www.openwall.com/lists/oss-security/2023/12/20/3
- https://www.openwall.com/lists/oss-security/2023/12/20/3
- https://www.paramiko.org/changelog.html
- https://www.paramiko.org/changelog.html
- https://www.reddit.com/r/sysadmin/comments/18idv52/cve202348795_why_is_this_cve_still_undisclosed/
- https://www.reddit.com/r/sysadmin/comments/18idv52/cve202348795_why_is_this_cve_still_undisclosed/
- https://www.suse.com/c/suse-addresses-the-ssh-v2-protocol-terrapin-attack-aka-cve-2023-48795/
- https://www.suse.com/c/suse-addresses-the-ssh-v2-protocol-terrapin-attack-aka-cve-2023-48795/
- https://www.terrapin-attack.com
- https://www.terrapin-attack.com
- https://www.theregister.com/2023/12/20/terrapin_attack_ssh
- https://www.theregister.com/2023/12/20/terrapin_attack_ssh
- https://www.vandyke.com/products/securecrt/history.txt
- https://www.vandyke.com/products/securecrt/history.txt
Closed bugs
Оторвать от sysvinit
Closed vulnerabilities
BDU:2024-04109
Уязвимость криптографической библиотеки OpenSSL, связанная с ошибками освобождения ресурсов, позволяющая нарушителю вызвать отказ в обслуживании
Modified: 2025-03-28
CVE-2024-2511
Issue summary: Some non-default TLS server configurations can cause unbounded memory growth when processing TLSv1.3 sessions Impact summary: An attacker may exploit certain server configurations to trigger unbounded memory growth that would lead to a Denial of Service This problem can occur in TLSv1.3 if the non-default SSL_OP_NO_TICKET option is being used (but not if early_data support is also configured and the default anti-replay protection is in use). In this case, under certain conditions, the session cache can get into an incorrect state and it will fail to flush properly as it fills. The session cache will continue to grow in an unbounded manner. A malicious client could deliberately create the scenario for this failure to force a Denial of Service. It may also happen by accident in normal operation. This issue only affects TLS servers supporting TLSv1.3. It does not affect TLS clients. The FIPS modules in 3.2, 3.1 and 3.0 are not affected by this issue. OpenSSL 1.0.2 is also not affected by this issue.
Modified: 2024-11-21
CVE-2024-4603
Issue summary: Checking excessively long DSA keys or parameters may be very slow. Impact summary: Applications that use the functions EVP_PKEY_param_check() or EVP_PKEY_public_check() to check a DSA public key or DSA parameters may experience long delays. Where the key or parameters that are being checked have been obtained from an untrusted source this may lead to a Denial of Service. The functions EVP_PKEY_param_check() or EVP_PKEY_public_check() perform various checks on DSA parameters. Some of those computations take a long time if the modulus (`p` parameter) is too large. Trying to use a very large modulus is slow and OpenSSL will not allow using public keys with a modulus which is over 10,000 bits in length for signature verification. However the key and parameter check functions do not limit the modulus size when performing the checks. An application that calls EVP_PKEY_param_check() or EVP_PKEY_public_check() and supplies a key or parameters obtained from an untrusted source could be vulnerable to a Denial of Service attack. These functions are not called by OpenSSL itself on untrusted DSA keys so only applications that directly call these functions may be vulnerable. Also vulnerable are the OpenSSL pkey and pkeyparam command line applications when using the `-check` option. The OpenSSL SSL/TLS implementation is not affected by this issue. The OpenSSL 3.0 and 3.1 FIPS providers are affected by this issue.
Modified: 2024-11-13
CVE-2024-4741
Issue summary: Calling the OpenSSL API function SSL_free_buffers may cause memory to be accessed that was previously freed in some situations Impact summary: A use after free can have a range of potential consequences such as the corruption of valid data, crashes or execution of arbitrary code. However, only applications that directly call the SSL_free_buffers function are affected by this issue. Applications that do not call this function are not vulnerable. Our investigations indicate that this function is rarely used by applications. The SSL_free_buffers function is used to free the internal OpenSSL buffer used when processing an incoming record from the network. The call is only expected to succeed if the buffer is not currently in use. However, two scenarios have been identified where the buffer is freed even when still in use. The first scenario occurs where a record header has been received from the network and processed by OpenSSL, but the full record body has not yet arrived. In this case calling SSL_free_buffers will succeed even though a record has only been partially processed and the buffer is still in use. The second scenario occurs where a full record containing application data has been received and processed by OpenSSL but the application has only read part of this data. Again a call to SSL_free_buffers will succeed even though the buffer is still in use. While these scenarios could occur accidentally during normal operation a malicious attacker could attempt to engineer a stituation where this occurs. We are not aware of this issue being actively exploited. The FIPS modules in 3.3, 3.2, 3.1 and 3.0 are not affected by this issue.