| Name | CVE-2019-20637 |
| Description | An issue was discovered in Varnish Cache before 6.0.5 LTS, 6.1.x and 6.2.x before 6.2.2, and 6.3.x before 6.3.1. It does not clear a pointer between the handling of one client request and the next request within the same connection. This sometimes causes information to be disclosed from the connection workspace, such as data structures associated with previous requests within this connection or VCL-related temporary headers. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 956305 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| varnish (PTS) | jessie, jessie (lts) | 4.0.2-1+deb8u1 | fixed |
| stretch (security), stretch (lts), stretch | 5.0.0-7+deb9u3 | vulnerable | |
| buster (security), buster, buster (lts) | 6.1.1-1+deb10u4 | vulnerable | |
| bullseye (security), bullseye | 6.5.1-1+deb11u3 | fixed | |
| bookworm | 7.1.1-1.1 | fixed | |
| sid, trixie | 7.6.0-2 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| varnish | source | wheezy | (unfixed) | end-of-life | ||
| varnish | source | jessie | (not affected) | |||
| varnish | source | (unstable) | 6.4.0-1 | 956305 |
[buster] - varnish <no-dsa> (Minor issue)
[stretch] - varnish <no-dsa> (Minor issue)
[jessie] - varnish <not-affected> (Vulnerability introduced later, PoC not leaking)
http://varnish-cache.org/security/VSV00004.html#vsv00004
https://github.com/varnishcache/varnish-cache/commit/bd7b3d6d47ccbb5e1747126f8e2a297f38e56b8c (6.x fix)
https://github.com/varnishcache/varnish-cache/commit/0c9c38513bdb7730ac886eba7563f2d87894d734 (test case / reproducer)
Introduced in https://github.com/varnishcache/varnish-cache/commit/62932b422f311ed1224f14a216169bcdc1b77a2d (5.0)
Case #3 implies labels introduced in https://github.com/varnishcache/varnish-cache/commit/34350d5e183ef4e04285729d1f63b784d1bc6454 (5.0)