What’s Vulnerable › Vulnerabilities
CVE-2025-23023: Anonymous cache poisoning via request headers in Discourse
- Severity: high (CVSS 8.2 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.3% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2025-02-04 · updated 2026-06-17
- Weakness: CWE-346
Description
Discourse is an open source platform for community discussion. In affected versions an attacker can carefully craft a request with the right request headers to poison the anonymous cache (for example, the cache may have a response with missing preloaded data). This issue only affects anonymous visitors of the site. This problem has been patched in the latest version of Discourse. Users are advised to upgrade. Users unable to upgrade may disable anonymous cache by setting the `DISCOURSE_DISABLE_ANON_CACHE` environment variable to a non-empty value.
Affected products
- discourse: before 3.3.2 — fixed in 3.3.2
How to fix
Upgrade to a fixed version: discourse 3.3.2. Check the vendor advisory for mitigations.
References
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