CVE-2021-36740
Publication date 14 July 2021
Last updated 24 July 2024
Ubuntu priority
Varnish Cache, with HTTP/2 enabled, allows request smuggling and VCL authorization bypass via a large Content-Length header for a POST request. This affects Varnish Enterprise 6.0.x before 6.0.8r3, and Varnish Cache 5.x and 6.x before 6.5.2, 6.6.x before 6.6.1, and 6.0 LTS before 6.0.8.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| varnish | 22.04 LTS jammy |
Not affected
|
| 20.04 LTS focal |
Fixed 6.2.1-2ubuntu0.1
|
|
| 18.04 LTS bionic |
Not affected
|
|
| 16.04 LTS xenial |
Not affected
|
|
| 14.04 LTS trusty |
Not affected
|
Notes
ebarretto
According to Debian: (HTTP/2 support is marked experimental in 5.0 and enabling is not recommended, code is quite different)
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
6.5 · Medium
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | Low |
| Integrity impact | Low |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
References
Related Ubuntu Security Notices (USN)
- USN-5474-1
- Varnish Cache vulnerabilities
- 8 June 2022
Other references
- https://varnish-cache.org/security/VSV00007.html
- https://github.com/varnishcache/varnish-cache/commit/9be22198e258d0e7a5c41f4291792214a29405cf (6.0.8)
- https://github.com/varnishcache/varnish-cache/commit/82b0a629f60136e76112c6f2c6372cce77b683be (6.5.2)
- https://github.com/varnishcache/varnish-cache/commit/82b0a629f60136e76112c6f2c6372cce77b683be
- https://github.com/varnishcache/varnish-cache/commit/9be22198e258d0e7a5c41f4291792214a29405cf
- https://docs.varnish-software.com/security/VSV00007/
- https://www.cve.org/CVERecord?id=CVE-2021-36740