CVE-2026-95691 openssl openssl: Use After Free
openssl openssl: no CVSS score yet. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
On this page
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.
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 9th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-416 Use After Free
- Published
- Modified
- Assigned by
- openssl (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
Ask an AI about this CVE
Show the prompt
Explain CVE-2026-95691 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-95691?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-95691?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-95691 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.
Badge for a README or a site
An image that stays current: it is drawn from the data each time it is fetched (a host that proxies images, as GitHub does, may show its copy for a while). Markdown:
[](https://cve.bz/cve/CVE-2026-95691)
HTML:
<a href="https://cve.bz/cve/CVE-2026-95691"><img src="https://cve.bz/cve/badge/CVE-2026-95691.svg" alt="CVE-2026-95691"></a>
Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| OpenSSL | from 4.1.0 before 4.1.1 |
| OpenSSL | from 4.0.0 before 4.0.4 |
| OpenSSL | from 3.5.0 before 3.5.10 |
Fix and patched versions
- Alpaquita, BellSoft Hardened Containers: fixed package versions per release
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12, 13, 14 | openssl | no fix listed | DEBIAN-CVE-2026-95691 |
| Ubuntu | 22.04:LTS, 24.04:LTS, Pro:20.04:LTS | edk2, openssl | no fix listed | UBUNTU-CVE-2026-95691 |
| Ubuntu | 26.04:LTS, 26.10 | edk2, openssl, edk2-hwe | no fix listed | UBUNTU-CVE-2026-95691 |
| Ubuntu | Pro:14.04:LTS, Pro:FIPS-updates:16.04:LTS, Pro:FIPS-updates:18.04:LTS and 4 more | openssl | no fix listed | UBUNTU-CVE-2026-95691 |
| Ubuntu | Pro:16.04:LTS | edk2, nodejs, openssl | no fix listed | UBUNTU-CVE-2026-95691 |
| Ubuntu | Pro:18.04:LTS | edk2, nodejs, openssl and 1 more | no fix listed | UBUNTU-CVE-2026-95691 |
| Ubuntu | Pro:22.04:LTS | nodejs | no fix listed | UBUNTU-CVE-2026-95691 |
| Ubuntu | Pro:FIPS-preview:22.04:LTS, Pro:FIPS-updates:22.04:LTS | openssl, openssl-fips | no fix listed | UBUNTU-CVE-2026-95691 |
| Ubuntu | Pro:FIPS-updates:24.04:LTS | openssl-fips | no fix listed | UBUNTU-CVE-2026-95691 |
| Alpaquita | 25, stream | openssl | 3.5.9-r1 | BELL-CVE-2026-95691 |
| BellSoft Hardened Containers | 25, stream | openssl | 3.5.9-r1 | BELL-CVE-2026-95691 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0; BellSoft's OSV database, MIT. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu · Alpaquita · BellSoft Hardened Containers.