CVE-2026-95691 is a vulnerability in OpenSSL
Published on November 10, 2026
Retransmitted QUIC CRYPTO Frames Can Cause DoS or One-byte Disclosure
Issue summary: A retransmitted QUIC CRYPTO frame can release packet storage
while the TLS record layer retains a direct pointer into that storage causing
use after free.
Impact summary: A malicious QUIC server can cause a heap-use-after-free read
in the OpenSSL QUIC client. The server can also identify one allocator-adjacent
byte through the client's protected Handshake response.
CWE: CWE-416: Use After Free
Description: During CRYPTO stream processing, a pointer into the first frame's
memory on the stream is lent to the TLS handshake processing. The memory
must remain stable until it is processed and released. However the processing
of retransmitted CRYPTO frames could release the memory if the retransmitted
frame fully overlapped the existing frame. This then causes use-after-free read
when the TLS handshake processing continues.
The use-after-free read can lead to a Denial-of-Service of the client
application or a minor leak of information about the heap memory contents
that might be overwritten with other data, subsequently allocated by
the application, to the peer.
FIPS impact: no
The FIPS module is not affected as the QUIC implementation is outside of
the OpenSSL FIPS module boundary.
Weakness Type
What is a Dangling pointer Vulnerability?
Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.
CVE-2026-95691 has been classified to as a Dangling pointer vulnerability or weakness.
Products Associated with CVE-2026-95691
Want to know whenever a new CVE is published for OpenSSL? stack.watch will email you.
Affected Versions
OpenSSL:- Version 4.1.0 and below 4.1.1 is affected.
- Version 4.0.0 and below 4.0.4 is affected.
- Version 3.5.0 and below 3.5.10 is affected.