Description
An issue was discovered in Varnish Cache before 6.0.6 LTS, 6.1.x and 6.2.x before 6.2.3, and 6.3.x before 6.3.2. It occurs when communication with a TLS termination proxy uses PROXY version 2. There can be an assertion failure and daemon restart, which causes a performance loss.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 13 | varnish | 6.4.0-1 | — |
| Debian 12 | varnish | 6.4.0-1 | — |
| Debian 10 | varnish | 6.1.1-1+deb10u4 | DLA-3208-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | varnish | 6.6.1-1ubuntu0.2 | USN-5474-1 |
| Ubuntu 20.04 LTS | varnish | 6.2.1-2ubuntu0.1 | USN-5474-2, USN-5474-1 |
| Ubuntu 18.04 LTS | varnish | 5.2.1-1ubuntu0.1 | USN-5474-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | varnish +2 | 6.0.6-2.module+el8.3.0+6843+b3b42fcc | RHSA-2020:4756 |
| RHEL 8 | varnish-modules | 0.15.0-5.module+el8.3.0+6843+b3b42fcc | RHSA-2020:4756 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | varnish | 6.0.6-2.module+el8.3.0+179+20b582cc | RLSA-2020:4756 |
| Rocky Linux 8 | varnish-modules | 0.15.0-5.module+el8.3.0+179+20b582cc | RLSA-2020:4756 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SUSE Package Hub 15 SP1 | varnish | 6.2.1-bp151.4.6.1 | openSUSE-SU-2020:0819-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.1 | varnish | 6.2.1-lp151.3.6.1 | openSUSE-SU-2020:0808-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | varnish +2 | 6.0.6-2.module+el8.3.0+7653+45014445 | ELSA-2020-4756 |
| Oracle Linux 8 | varnish-modules | 0.15.0-5.module+el8.3.0+7653+45014445 | ELSA-2020-4756 |
Advisories 9
- RHSA-2020:4756 Red Hat Security Advisory: varnish:6 security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- USN-5474-1 varnish vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- USN-5474-2 varnish regression Ubuntu Security Notices (USN) · Apr 22, 2026
- DLA-3208-1 varnish - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2020:4756 Moderate: varnish:6 security, bug fix, and enhancement update Rocky Linux Security Advisories · Feb 5, 2026
- openSUSE-SU-2020:0808-1 Security update for varnish SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:0819-1 Security update for varnish SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2022-0193 Red Hat Enterprise Linux: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 27, 2023
- ELSA-2020-4756 Moderate: varnish:6 security, bug fix, and enhancement update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Nov 10, 2020
References
- https://varnish-cache.org/security/VSV00005.html#vsv00005
- openSUSE-SU-2020:0819 vendor-advisory
- openSUSE-SU-2020:0808 vendor-advisory
- [debian-lts-announce] 20221127 [SECURITY] [DLA 3208-1] varnish security update mailing-list