Description
An issue was discovered in Varnish Cache before 6.0.4 LTS, and 6.1.x and 6.2.x before 6.2.1. An HTTP/1 parsing failure allows a remote attacker to trigger an assert by sending crafted HTTP/1 requests. The assert will cause an automatic restart with a clean cache, which makes it a Denial of Service attack.
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 | 6.2.1-1 | — |
| Debian 12 | varnish | 6.2.1-1 | — |
| Debian 10 | varnish | 6.1.1-1+deb10u1 | DSA-4514-1 |
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 |
| RHEL 3 | rh-varnish6 +2 | 4.1-6.el7 | RHEA-2020:2262 |
| RHEL 3 | rh-varnish6-varnish +3 | 6.0.6-1.el7 | RHEA-2020:2262 |
| RHEL 3 | rh-varnish6-varnish-modules | 0.15.0-6.el7 | RHEA-2020:2262 |
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-bp151.4.3.1 | openSUSE-SU-2019:2221-1 |
| SUSE Package Hub 15 | varnish | 6.2.1-bp151.4.3.1 | openSUSE-SU-2019:2221-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | varnish | 6.6.1-1.2 | openSUSE-SU-2024:11493-1 |
| openSUSE Tumbleweed | vinyl-cache | 9.0.0-1.1 | openSUSE-SU-2026:10751-1 |
| openSUSE Leap 15.1 | varnish | 6.2.1-lp151.3.3.1 | openSUSE-SU-2019:2184-1 |
| openSUSE Leap 15.0 | varnish | 6.2.1-lp151.3.3.1 | openSUSE-SU-2019:2184-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | varnish | 6.2.1-r0 | — |
| Alpine v3.23 | varnish | 6.2.1-r0 | — |
| Alpine v3.22 | varnish | 6.2.1-r0 | — |
| Alpine v3.21 | varnish | 6.2.1-r0 | — |
| Alpine v3.20 | varnish | 6.2.1-r0 | — |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | varnish | 6.2.1-r0 | — |
| Alpine v3.18 | varnish | 6.2.1-r0 | — |
| Alpine v3.17 | varnish | 6.2.1-r0 | — |
| Alpine v3.16 | varnish | 6.2.1-r0 | — |
| Alpine v3.15 | varnish | 6.2.1-r0 | — |
| Alpine v3.14 | varnish | 6.2.1-r0 | — |
| Alpine v3.13 | varnish | 6.2.1-r0 | — |
| Alpine v3.12 | varnish | 6.2.1-r0 | — |
| Alpine v3.11 | varnish | 6.2.1-r0 | — |
| Alpine v3.10 | varnish | 6.2.1-r0 | — |
| Alpine v3.9 | varnish | 6.2.1-r0 | — |
| Alpine v3.8 | varnish | 6.0.4-r0 | — |
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 10
- RHSA-2020:4756 Red Hat Security Advisory: varnish:6 security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHEA-2020:2262 Red Hat Enhancement Advisory: rh-varnish6 bug fix and enhancement update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- openSUSE-SU-2026:10751-1 libvinylapi3-9.0.0-1.1 on GA media SUSE / openSUSE Security Updates · May 12, 2026
- DSA-4514-1 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-2019:2221-1 Security update for varnish SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11493-1 libvarnishapi2-6.6.1-1.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:2184-1 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/VSV00003.html
- 20190904 [SECURITY] [DSA 4514-1] varnish security update mailing-list
- DSA-4514 vendor-advisory
- openSUSE-SU-2019:2184 vendor-advisory
- FEDORA-2019-8a85a90af6 vendor-advisory
- openSUSE-SU-2019:2221 vendor-advisory
- FEDORA-2019-a0a0cdef92 vendor-advisory
- FEDORA-2019-feec5e0afd vendor-advisory