Source: unbound
Version: 1.22.0-1
Severity: important
Tags: security upstream
X-Debbugs-Cc: [email protected], Debian Security Team <[email protected]>
Control: found -1 1.13.1-1+deb11u4
Control: found -1 1.13.1-1+deb11u2
Control: found -1 1.13.1-1

Hi,

The following vulnerability was published for unbound.

CVE-2025-5994[0]:
| 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.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2025-5994
    https://www.cve.org/CVERecord?id=CVE-2025-5994
[1] https://nlnetlabs.nl/downloads/unbound/CVE-2025-5994.txt

Please adjust the affected versions in the BTS as needed.

Regards,
Salvatore

Reply via email to