CVSS 3.1
6.5 mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NCVE-2021-36740
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.
Severity
- EPSS
- 1.6% chance of exploitation in the next 30 days; higher than 75% of CVEs (scores of 2026-10-31)
- CWE
- CWE-444
- Published
- Modified
- Record from
- the NVD, synced
Affected
- debian:debian_linux
- fedoraproject:fedora
- varnish-cache:varnish_cache
- varnish-software:varnish_cache
- varnish_cache_project:varnish_cache
References
- https://docs.varnish-software.com/security/VSV00007/
- https://github.com/varnishcache/varnish-cache/commit/82b0a629f60136e76112c6f2c6372cce77b683be
- https://github.com/varnishcache/varnish-cache/commit/9be22198e258d0e7a5c41f4291792214a29405cf
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/THV2DQA2GS65HUCKK4KSD2XLN3AAQ2V5/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZHBNLDEOTGYRIEQZBWV7F6VPYS4O2AAK/