CVE-2015-4050

Severity: medium (CVSS 4.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 8.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2015-06-02 · updated 2026-06-17
Weakness: CWE-284

Description

FragmentListener in the HttpKernel component in Symfony 2.3.19 through 2.3.28, 2.4.9 through 2.4.10, 2.5.4 through 2.5.11, and 2.6.0 through 2.6.7, when ESI or SSI support enabled, does not check if the _controller attribute is set, which allows remote attackers to bypass URL signing and security rules by including (1) no hash or (2) an invalid hash in a request to /_fragment.

Affected products

symfony: 2.3.19, 2.3.20, 2.3.21, 2.3.22, 2.3.23, 2.3.24 (+21)

References

http://lists.fedoraproject.org/pipermail/package-announce/2015-June/159513.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-June/159603.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-June/159610.html
http://symfony.com/blog/cve-2015-4050-esi-unauthorized-access
http://www.debian.org/security/2015/dsa-3276
http://www.securityfocus.com/bid/74928
http://lists.fedoraproject.org/pipermail/package-announce/2015-June/159513.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-June/159603.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-June/159610.html
http://symfony.com/blog/cve-2015-4050-esi-unauthorized-access
http://www.debian.org/security/2015/dsa-3276
http://www.securityfocus.com/bid/74928

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