GHSA-f93w-pcj3-rggc · Severity: high · Ecosystem: rust — Pingora vulnerable to cache poisoning via insecure-by-default cache key
A cache poisoning vulnerability has been found in the Pingora HTTP proxy framework’s default cache key construction. The issue occurs because the default HTTP cache key implementation generates cache keys using only the URI path, excluding critical factors such as the host header (authority). Operators relying on the default are vulnerable to cache poisoning, and cross-origin responses may be improperly served to users. Impact 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, poison the cache so that users from one tenant receive cached responses from another tenant * Cache poisoning attacks: Serve malicious content to legitimate users by poisoning shared cache entries Cloudflare's CDN infrastructure was 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. Mitigation: We strongly recommend Pingora users to upgrade to Pingora v0.8.0 or higher, which removes the insecure default cache key implementation. Users must now explicitly implement their own callback that includes appropriate factors such as Host header, origin server HTTP scheme, and other attributes their cache should vary on. Pingora users on previous versions may also remove any of their default CacheKey usage and implement their own that should at minimum include the host header / authority and upstream peer’s HTTP scheme.
Conclusion & alert: CVE-2026-2836 is rated Moderate Risk (44.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.39%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.01% | 0.39% | +0.38% |
| 2 | 2026-03-05 | — | 0.01% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.4 | 4.0 | HIGH |
|
— | — | [email protected] |
| 8.1 | 3.1 | HIGH |
|
2.8 | 5.2 | [email protected] |
GHSA-f93w-pcj3-rggc · Severity: high · Ecosystem: rust — Pingora vulnerable to cache poisoning via insecure-by-default cache key
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| cloudflare | pingora | < 0.8.0 | cpe:2.3:a:cloudflare:pingora:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://github.com/cloudflare/pingora | Product |