CVE-2024-23327: envoyproxy envoy · NULL Pointer Dereference
Affects envoyproxy envoySource CVE Database V5
Not known to be exploited · CVSS 7.5 High : upgrade to 1.26.7 soon.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 52% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.26.7
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 9 Feb 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 2026-10-26.
What to do
Upgrade envoyproxy/envoy to 1.26.7.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
GitHubenvoyproxy/envoypkg:github/envoyproxy/envoyOther 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
The primary and most effective mitigation is to upgrade Envoy Proxy to one of the patched versions: 1.26.7, 1.27.3, 1.28.1, or 1.29.1 or later. Organizations should prioritize this update in their patch management cycles. In environments where immediate upgrade is not feasible, consider temporarily disabling Proxy Protocol v2 on listeners and clusters to prevent the vulnerable code path from being exercised, though this may impact legitimate traffic handling and should be tested carefully. Additionally, implement network-level protections such as filtering or rate limiting traffic that could trigger the vulnerability, especially from untrusted sources. Monitoring Envoy logs and metrics for unexpected crashes or restarts can help detect exploitation attempts. Finally, incorporate this vulnerability into incident response and vulnerability management workflows to ensure timely detection and remediation.
Description
Envoy is a high-performance edge/middle/service proxy. When PPv2 is enabled both on a listener and subsequent cluster, the Envoy instance will segfault when attempting to craft the upstream PPv2 header. This occurs when the downstream request has a command type of LOCAL and does not have the protocol block. This issue has been addressed in releases 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.