CVE-2021-36740
First published: Tue Jul 13 2021(Updated: )
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.
Credit: cve@mitre.org
| Affected Software | Affected Version | How to fix |
|---|---|---|
| debian/varnish | 6.1.1-1+deb10u3 6.1.1-1+deb10u4 6.5.1-1+deb11u3 7.1.1-1.1 | |
| Varnish-cache Varnish Cache | >=6.0.0<6.0.8 | |
| Varnish-cache Varnish Cache | =6.0.8-r1 | |
| Varnish-cache Varnish Cache | =6.0.8-r2 | |
| Varnish-software Varnish Cache | >=6.0.0<=6.0.5 | |
| Varnish-software Varnish Cache | >=6.0.0<=6.0.7 | |
| Varnish Cache Project Varnish Cache | >=5.0.0<=5.2.1 | |
| Varnish Cache Project Varnish Cache | >=6.1.0<=6.6.0 | |
| Fedoraproject Fedora | =33 | |
| Fedoraproject Fedora | =34 | |
| Debian Debian Linux | =10.0 | |
| Debian Debian Linux | =11.0 |
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Reference Links
- https://varnish-cache.org/security/VSV00007.html
- https://github.com/varnishcache/varnish-cache/commit/9be22198e258d0e7a5c41f4291792214a29405cf
- https://github.com/varnishcache/varnish-cache/commit/82b0a629f60136e76112c6f2c6372cce77b683be
- https://security-tracker.debian.org/tracker/CVE-2021-36740
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=991040
- https://docs.varnish-software.com/security/VSV00007/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/THV2DQA2GS65HUCKK4KSD2XLN3AAQ2V5/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZHBNLDEOTGYRIEQZBWV7F6VPYS4O2AAK/
- https://www.debian.org/security/2022/dsa-5088
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZHBNLDEOTGYRIEQZBWV7F6VPYS4O2AAK/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/THV2DQA2GS65HUCKK4KSD2XLN3AAQ2V5/
Frequently Asked Questions
What is the vulnerability ID for this vulnerability?
The vulnerability ID is CVE-2021-36740.
What is the severity of CVE-2021-36740?
The severity of CVE-2021-36740 is medium (6.5).
Which software versions are affected by CVE-2021-36740?
Varnish Enterprise 6.0.x before 6.0.8r3, 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 are affected by CVE-2021-36740.
How can I fix CVE-2021-36740?
To fix CVE-2021-36740, you should update Varnish Cache to version 6.5.2, 6.6.1, or 6.0.8, depending on the software version you are using.
Where can I find more information about CVE-2021-36740?
You can find more information about CVE-2021-36740 on the Varnish Software website and the GitHub page of Varnish Cache.
- collector/debian-bugs
- alias/CVE-2021-36740
- collector/security-tracker-debian
- agent/type
- agent/remedy
- agent/first-publish-date
- agent/last-modified-date
- collector/nvd-index
- agent/software-canonical-lookup-request
- agent/weakness
- agent/references
- agent/severity
- agent/author
- agent/softwarecombine
- agent/tags
- agent/description
- agent/event
- collector/mitre-cve
- source/MITRE
- package-manager/debian
- vendor/varnish-cache
- canonical/varnish-cache varnish cache
- version/varnish-cache varnish cache/6.0.0
- version/varnish-cache varnish cache/6.0.8-r1
- version/varnish-cache varnish cache/6.0.8-r2
- vendor/varnish-software
- canonical/varnish-software varnish cache
- version/varnish-software varnish cache/6.0.0
- version/varnish-software varnish cache/6.0.5
- version/varnish-software varnish cache/6.0.7
- vendor/varnish cache project
- canonical/varnish cache project varnish cache
- version/varnish cache project varnish cache/5.0.0
- version/varnish cache project varnish cache/5.2.1
- version/varnish cache project varnish cache/6.1.0
- version/varnish cache project varnish cache/6.6.0
- vendor/fedoraproject
- canonical/fedoraproject fedora
- version/fedoraproject fedora/33
- version/fedoraproject fedora/34
- vendor/debian
- canonical/debian debian linux
- version/debian debian linux/10.0
- version/debian debian linux/11.0