CVE-2026-34183

Description

Issue summary: Remote peer may exhaust heap memory of the QUIC server or client by flooding it with packets containing PATH_CHALLENGE frames. Impact summary: A malicious remote peer can cause an unbounded memory allocation which can lead to an abnormal termination of the application acting as a QUIC client or server and a Denial of Service. A remote peer may exhaust heap memory by flooding the local QUIC stack with PATH_CHALLENGE frames. The local QUIC stack allocates a PATH_RESPONSE frame for every PATH_CHALLENGE it receives. The allocated PATH_RESPONSE frame gets freed only when the remote peer acknowledges reception of the PATH_RESPONSE frame which will not be done by a malicious peer. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue. The QUIC stack is outside of OpenSSL FIPS module boundary.

How to fix CVE-2026-34183

To remediate CVE-2026-34183, upgrade the affected package to a fixed version below.

• —upgrade to 3.5.7-r0 or later
• —upgrade to 3.5.6-1~deb13u2 or later

Is CVE-2026-34183 being exploited?

No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-34183.

Affected packages (2)

• from 0, < 3.5.7-r0
• from 0, < 3.5.6-1~deb13u2

CVSS scores

References (2)

• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2026-34183
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2026-34183