An issue was discovered in Varnish Cache before 6.0.6 LTS, 6.1.x and 6.2.x before 6.2.3…
Priority LOW 37CWE-617Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 1 fixed, 1 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-617.
Summary
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.
Why it matters now
EPSS 0.02159 82nd percentileScored 2026-11-07
Fix Partial Red Hat: 1 advisoryRed Hat: 1 fixed, 1 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:varnish-cache:varnish_cache:*:*:*:*:-:*:*:* | 6.1.0 to before 6.2.3; 6.3.0 to before 6.3.2 | Vulnerable | Varnish-cache |
| cpe:2.3:a:varnish-software:varnish_cache:*:*:*:*:lts:*:*:* | 6.0.0 to before 6.0.6 | Vulnerable | varnish-software |
| cpe:2.3:a:opensuse:backports_sle:15.0:sp1:*:*:*:*:*:* | 15.0 sp1 | Vulnerable | openSUSE |
| cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* | 15.1 | Vulnerable | openSUSE |
| cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* | 10.0 | Vulnerable | Debian |
- cpe:2.3:a:varnish-cache:varnish_cache:*:*:*:*:-:*:*:* Versions 6.1.0 to before 6.2.3; 6.3.0 to before 6.3.2 Vulnerable ·Varnish-cache
- cpe:2.3:a:varnish-software:varnish_cache:*:*:*:*:lts:*:*:* Versions 6.0.0 to before 6.0.6 Vulnerable ·varnish-software
- cpe:2.3:a:opensuse:backports_sle:15.0:sp1:*:*:*:*:*:* Versions 15.0 sp1 Vulnerable ·openSUSE
- cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* Versions 15.1 Vulnerable ·openSUSE
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
Remediation
Red Hat 1 advisory
- RHSA-2020:4756 Released 2020-11-04 · Red Hat rating Moderatevarnish:6 security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 8) varnish-6.0.6-2.module+el8.3.0+6843+b3b42fcc.aarch64::varnish:6, varnish-6.0.6-2.module+el8.3.0+6843+b3b42fcc.ppc64le::varnish:6, varnish-6.0.6-2.module+el8.3.0+6843+b3b42fcc.s390x::varnish:6 +15
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Software Collections | Affected | No fix yet |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2020:4756 |
Timeline
- 2026-10-02 Threatist record created from CVE-2020-11653
- 2026-10-03 Alias added: GHSA-jg36-89rw-qgr3
References
Sources
- CVE-2020-11653 · CVE Program
- CVE-2020-11653 · NVD
- FIRST EPSS
- GHSA-jg36-89rw-qgr3 · GitHub Advisory Database · CC BY 4.0
- CVE-2020-11653 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences