CVE-2026-41246Contour: Lua code injection via Cookie Path Rewrite Policy
- 8.1HighCVSS base score
- 0.49%Exploitation in 30 daysEPSS · top 57% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Contour is a Kubernetes ingress controller using Envoy proxy. From v1.19.0 to before v1.33.4, v1.32.5, and v1.31.6, Contour's Cookie Rewriting feature is vulnerable to Lua code injection. An attacker with RBAC permissions to create or modify HTTPProxy resources can craft a malicious value in spec.routes[].cookieRewritePolicies[].pathRewrite.value or spec.routes[].services[].cookieRewritePolicies[].pathRewrite.value that results in arbitrary code execution in the Envoy proxy. The cookie rewriting feature is internally implemented using Envoy's HTTP Lua filter. User-controlled values are interpolated into Lua source code using Go text/template without sufficient sanitization. The injected code only executes when processing traffic on the attacker's own route, which they already control. However, since Envoy runs as shared infrastructure, the injected code can also read Envoy's xDS client credentials from the filesystem or cause denial of service for other tenants sharing the Envoy instance. This vulnerability is fixed in v1.33.4, v1.32.5, and v1.31.6.
Timeline
ID reserved
By GitHub_M
- 5 days later
· 5 days later
Published
- 3 months later
· 3 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
| redhat-SADPADP (enrichment) | 3.1 | High8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
| NVDNVD · Modified | 3.1 | High8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.49% · top 57% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.1.
Affected products
- affected >= 1.33.0, < 1.33.4
- affected >= 1.32.0, < 1.32.5
- affected >= 1.19.0, < 1.31.6
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/projectcontour/contourGHSA-x4mj-7f9g-29h4 (opens in a new tab)
References
References7
- https://github.com/projectcontour/contour/security/advisories/GHSA-x4mj-7f9g-29h4 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/projectcontour/contour/releases/tag/v1.31.6 (opens in a new tab)x_refsource_MISC
- https://github.com/projectcontour/contour/releases/tag/v1.32.5 (opens in a new tab)x_refsource_MISC
- https://github.com/projectcontour/contour/releases/tag/v1.33.4 (opens in a new tab)x_refsource_MISC
- https://access.redhat.com/security/cve/CVE-2026-41246 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2461257 (opens in a new tab)issue-trackingx_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41246.json (opens in a new tab)x_sadp-csaf-vex
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-25280 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-x4mj-7f9g-29h4 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-41246)Record last updated .