varnish-software CVE Vulnerabilities & Metrics

Focus on varnish-software vulnerabilities and metrics.

Last updated: 16 Apr 2025, 22:25 UTC

About varnish-software Security Exposure

This page consolidates all known Common Vulnerabilities and Exposures (CVEs) associated with varnish-software. We track both calendar-based metrics (using fixed periods) and rolling metrics (using gliding windows) to give you a comprehensive view of security trends and risk evolution. Use these insights to assess risk and plan your patching strategy.

For a broader perspective on cybersecurity threats, explore the comprehensive list of CVEs by vendor and product. Stay updated on critical vulnerabilities affecting major software and hardware providers.

Global CVE Overview

Total varnish-software CVEs: 10
Earliest CVE date: 04 Aug 2017, 09:29 UTC
Latest CVE date: 21 Mar 2025, 07:15 UTC

Latest CVE reference: CVE-2025-30347

Rolling Stats

30-day Count (Rolling): 2
365-day Count (Rolling): 2

Calendar-based Variation

Calendar-based Variation compares a fixed calendar period (e.g., this month versus the same month last year), while Rolling Growth Rate uses a continuous window (e.g., last 30 days versus the previous 30 days) to capture trends independent of calendar boundaries.

Variations & Growth

Month Variation (Calendar): 0%
Year Variation (Calendar): 100.0%

Month Growth Rate (30-day Rolling): 0.0%
Year Growth Rate (365-day Rolling): 100.0%

Monthly CVE Trends (current vs previous Year)

Annual CVE Trends (Last 20 Years)

Critical varnish-software CVEs (CVSS ≥ 9) Over 20 Years

CVSS Stats

Average CVSS: 3.56

Max CVSS: 7.8

Critical CVEs (≥9): 0

CVSS Range vs. Count

Range Count
0.0-3.9 4
4.0-6.9 5
7.0-8.9 1
9.0-10.0 0

CVSS Distribution Chart

Top 5 Highest CVSS varnish-software CVEs

These are the five CVEs with the highest CVSS scores for varnish-software, sorted by severity first and recency.

All CVEs for varnish-software

Varnish Enterprise before 6.0.13r13 allows remote attackers to obtain sensitive information via an out-of-bounds read for range requests on ephemeral MSE4 stevedore objects.

Varnish Cache before 7.6.2 and Varnish Enterprise before 6.0.13r10 allow client-side desync via HTTP/1 requests.

libvmod-digest before 1.0.3, as used in Varnish Enterprise 6.0.x before 6.0.11r5, has an out-of-bounds memory access during base64 decoding, leading to both authentication bypass and information disclosure; however, the exact attack surface will depend on the particular VCL (Varnish Configuration Language) configuration in use.

An HTTP Request Forgery issue was discovered in Varnish Cache 5.x and 6.x before 6.0.11, 7.x before 7.1.2, and 7.2.x before 7.2.1. An attacker may introduce characters through HTTP/2 pseudo-headers that are invalid in the context of an HTTP/1 request line, causing the Varnish server to produce invalid HTTP/1 requests to the backend. This could, in turn, be used to exploit vulnerabilities in a server behind the Varnish server. Note: the 6.0.x LTS series (before 6.0.11) is affected.

CVE-2022-23959 varnish-software vulnerability CVSS: 6.4 26 Jan 2022, 01:15 UTC

In Varnish Cache before 6.6.2 and 7.x before 7.0.2, Varnish Cache 6.0 LTS before 6.0.10, and and Varnish Enterprise (Cache Plus) 4.1.x before 4.1.11r6 and 6.0.x before 6.0.9r4, request smuggling can occur for HTTP/1 connections.

CVE-2021-36740 varnish-software vulnerability CVSS: 6.4 14 Jul 2021, 17:15 UTC

Varnish Cache, with HTTP/2 enabled, allows request smuggling and VCL authorization bypass via a large Content-Length header for a POST request. This affects Varnish Enterprise 6.0.x before 6.0.8r3, and Varnish Cache 5.x and 6.x before 6.5.2, 6.6.x before 6.6.1, and 6.0 LTS before 6.0.8.

CVE-2020-11653 varnish-software vulnerability CVSS: 5.0 08 Apr 2020, 23:15 UTC

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.

CVE-2019-20637 varnish-software vulnerability CVSS: 5.0 08 Apr 2020, 23:15 UTC

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.

CVE-2019-15892 varnish-software vulnerability CVSS: 7.8 03 Sep 2019, 21:15 UTC

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.

CVE-2017-12425 varnish-software vulnerability CVSS: 5.0 04 Aug 2017, 09:29 UTC

An issue was discovered in Varnish HTTP Cache 4.0.1 through 4.0.4, 4.1.0 through 4.1.7, 5.0.0, and 5.1.0 through 5.1.2. A wrong if statement in the varnishd source code means that particular invalid requests from the client can trigger an assert, related to an Integer Overflow. This causes the varnishd worker process to abort and restart, losing the cached contents in the process. An attacker can therefore crash the varnishd worker process on demand and effectively keep it from serving content - a Denial-of-Service attack. The specific source-code filename containing the incorrect statement varies across releases.