CVE-2026-34475 Varnish Cache before 8.0.1 and Varnish Enterprise before 6.0.16r12, in certain unchecked req.url scenarios, mishandle URLs with a path of /
Medium 5.4
Published
Updated
Check this codebase for CVE-2026-34475 and fix it if it is affected.
What it is: CVE-2026-34475 is a medium-severity vulnerability in varnish-software Varnish Cache, published on 27 Mar 2026.
Exploitation: There is no known exploitation of CVE-2026-34475 in the wild and no public exploit code.
Affected product: varnish-software Varnish Cache. No package-level version data is available, so check the vendor advisory linked from the reference page.
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2026-34475/ (Markdown: https://insights.sbomify.com/CVE-2026-34475/index.md)
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-34475?
CVE-2026-34475 is a medium-severity vulnerability in varnish-software Varnish Cache, published on 27 Mar 2026.
Official description
Varnish Cache before 8.0.1 and Varnish Enterprise before 6.0.16r12, in certain unchecked req.url scenarios, mishandle URLs with a path of / for HTTP/1.1, potentially leading to cache poisoning or authentication bypass.
Weakness: CWE-180
Which versions are affected by CVE-2026-34475?
It affects 2 products.
Products include Varnish-Software Varnish Enterprise, Vinyl-Cache Vinyl Cache.
How do I fix CVE-2026-34475?
Upgrade to a fixed version.
Is CVE-2026-34475 being exploited?
There is no known exploitation of CVE-2026-34475 in the wild and no public exploit code.
Other vulnerabilities in varnish-software Varnish Cache
Sources
Also known as DEBIAN-CVE-2026-34475, GHSA-m9gq-cmcj-p62x, OESA-2026-2677, OESA-2026-3045, ROOT-OS-DEBIAN-11-CVE-2026-34475, ROOT-OS-DEBIAN-12-CVE-2026-34475 and 1 more.