CVE-2026-75804: Issue summary · OpenSSL QUIC stack does not enforce connection level flow control for streams
Affects nodejsSource GCVE Database
Not known to be exploited · CVSS 5.3 Medium : upgrade to 3.5.5-1ubuntu3.6 when convenient.
Data as of 12 Nov 2026, 23:24 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 45% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.5.5-1ubuntu3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 29 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Upgrade the Ubuntu openssl package to 3.5.5-1ubuntu3.6.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10edk2pkg:deb/ubuntu/edk2?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.10edk2-hwepkg:deb/ubuntu/edk2-hwe?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSedk2pkg:deb/ubuntu/edk2?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSedk2-hwepkg:deb/ubuntu/edk2-hwe?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSopensslpkg:deb/ubuntu/openssl?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu Pro 22.04 LTSnodejspkg:deb/ubuntu/nodejs?arch=source&distro=esm-apps/jammyOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available for this vulnerability. Users should apply the official updates to the affected Node.js versions to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
Description
A vulnerability in the OpenSSL QUIC stack used by Node.js allows a remote peer to bypass connection-level flow control for streams. This can lead to excessive memory allocation on the local system, potentially up to 100MB per connection instead of the intended 768 KiB. Exploitation requires specific conditions involving multiple streams and data patterns. The OpenSSL FIPS module is not affected as the QUIC implementation lies outside its boundary. The issue has a CVSS score of 5.3 (low severity) and affects multiple specific Node.js versions. A patch is available to address this vulnerability.
References
- nvd.nist.gov/vuln/detail/CVE-2026-75804 (opens in a new tab)
- github.com/openssl/openssl/commit/2e8f54666b3fb7b05ff5f58aa6cac9285163654e (opens in a new tab)
- github.com/openssl/openssl/commit/4533ee8a5686c953ed3b644738ac4bdf20806538 (opens in a new tab)
- github.com/openssl/openssl/commit/64d3102fb5b54311e92517f26ba00169d719e74a (opens in a new tab)
- github.com/openssl/openssl/commit/f9eaecf5bdd6692da052bc65b0332af2a938ac03 (opens in a new tab)
- openssl-library.org/news/secadv/20260929.txt (opens in a new tab)
- ubuntu.com/security/CVE-2026-75804 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-75804 (opens in a new tab)
- ubuntu.com/security/notices/USN-8847-1 (opens in a new tab)