All errata/p11/ALT-PU-2025-9884-3
ALT-PU-2025-9884-3

Package update unbound in branch p11

Version1.23.1-alt1
Task#391280
Published2026-02-04
Max severityHIGH
Severity:

Closed issues (2)

BDU:2025-12600
HIGH7.5

Уязвимость DNS-сервера Unbound, связанная с загрузкой внешних ненадёжных данных вместе с надёжными данными, позволяющая нарушителю осуществлять атаки отравления кэша

Published: 2025-10-08Modified: 2026-03-04
CVSS 3.xHIGH 7.5
CVSS:3.x/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS 2.0HIGH 7.8
CVSS:2.0/AV:N/AC:L/Au:N/C:N/I:C/A:N
References
CVE-2025-5994
HIGH8.7

A multi-vendor cache poisoning vulnerability named 'Rebirthday Attack' has been discovered in caching resolvers that support EDNS Client Subnet (ECS). Unbound is also vulnerable when compiled with ECS support, i.e., '--enable-subnet', AND configured to send ECS information along with queries to upstream name servers, i.e., at least one of the 'send-client-subnet', 'client-subnet-zone' or 'client-subnet-always-forward' options is used. Resolvers supporting ECS need to segregate outgoing queries to accommodate for different outgoing ECS information. This re-opens up resolvers to a birthday paradox attack (Rebirthday Attack) that tries to match the DNS transaction ID in order to cache non-ECS poisonous replies.

Published: 2025-07-16Modified: 2026-04-15
CVSS 4.0HIGH 8.7
CVSS:4.0/CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:U/V:C/RE:X/U:X
References