CVE-2021-25219
bind9 - security update
5.3
MEDIUM
CVSS 3.1
EPSS 1.0%
Description
In BIND 9.3.0 -> 9.11.35, 9.12.0 -> 9.16.21, and versions 9.9.3-S1 -> 9.11.35-S1 and 9.16.8-S1 -> 9.16.21-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.18 of the BIND 9.17 development branch, exploitation of broken authoritative servers using a flaw in response processing can cause degradation in BIND resolver performance. The way the lame cache is currently designed makes it possible for its internal data structures to grow almost infinitely, which may cause significant delays in client query processing.
How to fix CVE-2021-25219
To remediate CVE-2021-25219, upgrade the affected package to a fixed version below.
- —upgrade to 9.16.27-r0 or later
- —upgrade to 1:9.16.22-1~deb11u1 or later
- —upgrade to 1:9.11.5.P4+dfsg-5.1+deb10u6 or later
Is CVE-2021-25219 being exploited?
Low — EPSS is 1.0%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0, < 9.16.27-r0
- from 0, < 1:9.16.22-1~deb11u1
- from 0, < 1:9.11.5.P4+dfsg-5.1+deb10u6
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |