Pingora vulnerable to cache poisoning via insecure-by-default cache key

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

8.4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:H/SI:H/SA:N · score source

EPSS

• CVE-2026-2836: 0.40% estimated exploitation activity in the next 30 days; percentile 33.83 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact Pingora versions prior to 0.8.0 generated cache keys using only the URI path, excluding critical factors such as the host header. This allows an attacker to poison the cache and serve cross-origin responses to users. This vulnerability affects users of Pingora's alpha proxy caching feature who relied on the default CacheKey implementation. An attacker could exploit this for cross-tenant data leakage in multi-tenant deployments, or serve malicious content to legitimate users by poisoning shared cache entries. Note: Cloudflare customers and Cloudflare's CDN infrastructure were not affected by this vulnerability, as Cloudflare's default cache key implementation uses multiple factors to prevent cache key poisoning and never made use of the previously provided default. Patches We strongly suggest users should upgrade to Pingora v.0.8.0 or higher, which removes the default CacheKey implementation. Workarounds Do not rely on the provided CacheKey default, and at minimum use the host…

Published by the source

5 Mar 2026, 20:57 UTC

Last modified by the source

9 Mar 2026, 20:46 UTC

Source last checked

26 Oct 2026, 15:42 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-f93w-pcj3-rggc

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# Patch Next advisory brief: CVE-2026-2836

Advisory: Pingora vulnerable to cache poisoning via insecure-by-default cache key
IDs: CVE-2026-2836, GHSA-f93w-pcj3-rggc
Record: https://patchnext.com/advisories/cve-2026-2836 (revision 1, source checked 26 Oct 2026, 15:42 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.4)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: pingora-cache 0.8.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io pingora-cache: affected <= 0.7.0; fixed in 0.8.0

## Suggested inspection (read-only)
- crates.io pingora-cache: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on pingora-cache.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-f93w-pcj3-rggc (GitHub-reviewed advisory GHSA-f93w-pcj3-rggc lists affected ranges: crates.io pingora-cache >=0 <=0.7.0)

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