Contour: Lua code injection via Cookie Path Rewrite Policy
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 1.33.4, 1.32.5, 1.31.6
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
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
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- projectcontour contour
From 1.33.0 · fixed in 1.33.4; From 1.32.0 · fixed in 1.32.5; From 1.19.0 · fixed in 1.31.6
- github.com/projectcontour/contourGo
From 1.19.0 · fixed in 1.31.6
- github.com/projectcontour/contourGo
From 1.32.0 · fixed in 1.32.5
- github.com/projectcontour/contourGo
From 1.33.0 · fixed in 1.33.4
- github.com/projectcontour/contourGo
From 1.19.0 · fixed in 1.31.6; From 1.32.0 · fixed in 1.32.5; From 1.33.0 · fixed in 1.33.4