Use-after-free in c-ares - #VU156262

Vulnerability details

The vulnerability allows a remote attacker to cause a denial of service by crashing an application using c-ares.

The vulnerability exists due to use-after-free in the c-ares query cache when a completion callback reconfigures servers or starts another lookup, causing the cached answer to be freed before the callback finishes reading it. A remote attacker can trigger this sequence in an affected application to cause a denial of service through a process crash.

Affected software

Remediation

External References

• https://github.com/c-ares/c-ares/security/advisories/GHSA-grv7-fq5q-9vfc
• https://github.com/c-ares/c-ares/commit/a21160045f9d7039225fa285be7cb1b02173a3a5

Related Security Bulletins

• Multiple vulnerabilities in c-ares