c-ares has a use-after-free in read_answers()
ディストリビューション別の修正状況
各ディストリビューションが公開している、この CVE の修正パッケージ
- Alpine Linux ALPINE-CVE-2025-31498 c-ares 修正版: 1.34.5-r0
- Debian DEBIAN-CVE-2025-31498 c-ares 修正版: 1.34.5-1
原文の説明 取得元が公開している説明をそのまま載せています (多くは英語)。
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.
出典: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
参照URL
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov
- patch github.com
- patch github.com
- web openwall.com