ALPINE-CVE-2025-31498
ALPINE-CVE-2025-31498
This page contains facts from public vulnerability sources. Check the original advisory before updating.
c-ares is an asynchronous resolver library. From 1.32.3 through 1.34.4, there is a use-after-free in read_answers() when process_answer() may re-enqueue a query either due to a DNS Cookie Failure or when the upstream server does not properly support EDNS, or possibly on TCP queries if the remote closed the connection immediately after a response. If there was an issue trying to put that new transaction on the wire, it would close the connection handle, but read_answers() was still expecting the connection handle to be available to possibly dequeue other responses. In theory a remote attacker might be able to trigger this by flooding the target with ICMP UNREACHABLE packets if they also control the upstream nameserver and can return a result with one of those conditions, this has been untested. Otherwise only a local attacker might be able to change system behavior to make send()/write() return a failure condition. This vulnerability is fixed in 1.34.5.
CVSS 8.3 · High · Fix available
- Published
- Updated
Stack: system
Affected products and versions
c-ares Alpine:v3.21
- Affected ranges
- ECOSYSTEM: < 1.34.5-r0
Update to 1.34.5-r0
c-ares Alpine:v3.22
- Affected ranges
- ECOSYSTEM: < 1.34.5-r0
Update to 1.34.5-r0
c-ares Alpine:v3.23
- Affected ranges
- ECOSYSTEM: < 1.34.5-r0
Update to 1.34.5-r0
c-ares Alpine:v3.24
- Affected ranges
- ECOSYSTEM: < 1.34.5-r0
Update to 1.34.5-r0