Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Symfony's http-kernel and symfony packages, versions 4.3.0 up to 4.4.13 and 5.0.0 up to 5.1.5, are affected. When CachingHttpClient is used, an attacker who controls the response to a request it makes can exploit internal cache headers in HttpCache to achieve remote code execution. Upgrade to symfony/http-kernel or symfony/symfony 4.4.13 or 5.1.5, or later.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 8.0 | High | 3.1 | CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.030, the 87th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:25 UTC First seen by agentprime
- 31 Oct 2026, 14:25 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-754h-5r27-7x3r
- OSV: GHSA-754h-5r27-7x3r
- github.com/symfony/symfony/security/advisories/GHSA-754h-5r27-7x3r
- nvd.nist.gov/vuln/detail/CVE-2020-15094
- github.com/symfony/symfony/commit/d9910e0b33a2e0f993abff41c6fbc86951b66d78
- github.com/FriendsOfPHP/security-advisories/blob/master/symfony/http-kernel/CVE-2020-15094.yaml
- github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2020-15094.yaml
- github.com/symfony/symfony
- lists.fedoraproject.org/archives/list/[email protected]/message/HNGUWOEETOFVH4PN3I3YO4QZHQ4AUKF3
- lists.fedoraproject.org/archives/list/[email protected]/message/VAQJXAKWPMWB7OL6QPG2ZSEQZYYPU5RC
- packagist.org/packages/symfony/http-kernel
- packagist.org/packages/symfony/symfony
- symfony.com/cve-2020-15094