CVE-2021-36740 describes a request smuggling and VCL authorization bypass vulnerability in Varnish Cache, specifically when HTTP/2 is enabled. This flaw, affecting Varnish Enterprise and Varnish Cache versions including 5.x, 6.x, and 6.0 LTS, is triggered by a large Content-Length header in a POST request. With a CVSS score of 6.5 (Medium), it can be exploited remotely with low attack complexity, potentially leading to information disclosure and unauthorized access (CWE-444). There is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion surrounding this vulnerability.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
>= 6.0.0, < 6.0.8CPE matchmatch criteria | cpe:2.3:a:varnish-cache:varnish_cache:*:*:*:*:plus:*:*:* | ||
6.0.8CPE matchmatch criteria | cpe:2.3:a:varnish-cache:varnish_cache:6.0.8:r1:*:*:plus:*:*:* | ||
6.0.8CPE matchmatch criteria | cpe:2.3:a:varnish-cache:varnish_cache:6.0.8:r2:*:*:plus:*:*:* | ||
>= 6.0.0, <= 6.0.5CPE matchmatch criteria | cpe:2.3:a:varnish-software:varnish_cache:*:*:*:*:*:*:*:* | ||
>= 6.0.0, <= 6.0.7CPE matchmatch criteria | cpe:2.3:a:varnish-software:varnish_cache:*:*:*:*:lts:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.