CVE-2022-3924 named configured to answer from stale cache may terminate unexpectedly at recursive-clients soft quota
A race condition in BIND 9 resolvers with stale answers enabled can cause an assertion failure and unexpected termination under high recursive load.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-3924?
CVE-2022-3924 is a high-severity vulnerability in Isc Bind, published on 25 Jan 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
This issue can affect BIND 9 resolvers with `stale-answer-enable yes;` that also make use of the option `stale-answer-client-timeout`, configured with a value greater than zero.
If the resolver receives many queries that require recursion, there will be a corresponding increase in the number of clients that are waiting for recursion to complete. If there are sufficient clients already waiting when a new client query is received so that it is necessary to SERVFAIL the longest waiting client (see BIND 9 ARM `recursive-clients` limit and soft quota), then it is possible for a race to occur between providing a stale answer to this older client and sending an early timeout SERVFAIL, which may cause an assertion failure. This issue affects BIND 9 versions 9.16.12 through 9.16.36, 9.18.0 through 9.18.10, 9.19.0 through 9.19.8, and 9.16.12-S1 through 9.16.36-S1.
Weakness: CWE-617
Which versions are affected by CVE-2022-3924?
It affects 1 product.
Products include Isc Bind.
How do I fix CVE-2022-3924?
Upgrade to a fixed version.
Is CVE-2022-3924 being exploited?
There is no known exploitation of CVE-2022-3924 in the wild and no public exploit code.
Other vulnerabilities in Isc Bind
Sources
Also known as ALPINE-CVE-2022-3924, AZL-13227, DEBIAN-CVE-2022-3924, GHSA-29px-hvx8-j7xf, UBUNTU-CVE-2022-3924.