Use After Free in Envoyproxy Envoy
CVE-2022-29227
Envoy is a cloud-native high-performance edge/middle/service proxy. In versions prior to 1.22.1 if Envoy attempts to send an internal redirect of an HTTP request consisting of more than HTTP headers, there’s a lifetime bug which can be triggered. If while replaying the request Envoy sends a local reply when the redirect headers are processed, the downstream state indicates that the downstream stream is not complete. On sending the local reply, Envoy will attempt to reset the upstream stream, but as it is actually complete, and deleted, this result in a use-after-free. Users are advised to upgrade. Users unable to upgrade are advised to disable internal redirects if crashes are observed.
Vulnerability class: Use-After-Free
EPSS: 0.011 (63.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Envoyproxy Envoy — versions < 1.22.1
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
- security-advisories@github.com (Patch, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2022-29227?
- CVE-2022-29227 is a high-severity vulnerability in Envoyproxy Envoy, classified under Use After Free. CVSS score: 7.5/10. Published 2022-06-09.
- How severe is CVE-2022-29227?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2022-29227 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.