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.
CVE-2015-4050
- No confirmed exploitation signals yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- —
- EG Score
- 0.0(none)
- EPSS
- 94.3%
- KEV
- Not listed
Published
June 2, 2015
Last Modified
May 6, 2026
References (12)
- cve@mitrehttp://lists.fedoraproject.org/pipermail/package-announce/2015-June/159513.html
- cve@mitrehttp://lists.fedoraproject.org/pipermail/package-announce/2015-June/159603.html
- cve@mitrehttp://lists.fedoraproject.org/pipermail/package-announce/2015-June/159610.html
- cve@mitrehttp://symfony.com/blog/cve-2015-4050-esi-unauthorized-access
- cve@mitrehttp://www.debian.org/security/2015/dsa-3276
- cve@mitrehttp://www.securityfocus.com/bid/74928
- af854a3a-2127-422b-91ae-364da2661108http://lists.fedoraproject.org/pipermail/package-announce/2015-June/159513.html
- af854a3a-2127-422b-91ae-364da2661108http://lists.fedoraproject.org/pipermail/package-announce/2015-June/159603.html
- af854a3a-2127-422b-91ae-364da2661108http://lists.fedoraproject.org/pipermail/package-announce/2015-June/159610.html
- af854a3a-2127-422b-91ae-364da2661108http://symfony.com/blog/cve-2015-4050-esi-unauthorized-access
- af854a3a-2127-422b-91ae-364da2661108http://www.debian.org/security/2015/dsa-3276
- af854a3a-2127-422b-91ae-364da2661108http://www.securityfocus.com/bid/74928
Affected Packages
(2 across 1 ecosystem)
Packagist(2)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| symfony/http-kernel | v2.4.10, v2.4.9 | — | — |
| symfony/symfony | v2.6.0 ... v2.6.7 (8 versions) | 2.6.8 | — |
Data Freshness Timeline
(refreshed 7× in last 7d / 37× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-11 08:23 UTCEPSS rescore
- 2026-07-09 19:05 UTCEPSS rescore
- 2026-07-08 15:10 UTCEPSS rescore
- 2026-07-07 13:42 UTCEPSS rescore
- 2026-07-06 16:24 UTCEPSS rescore
- 2026-07-06 02:20 UTCEPSS rescore
- 2026-07-05 02:26 UTCEPSS rescore
- 2026-07-04 06:27 UTCEPSS rescore
- 2026-07-02 15:21 UTCEPSS rescore
- 2026-07-01 15:02 UTCEPSS rescore
- 2026-07-01 15:02 UTCEPSS rescore
- 2026-06-30 23:19 UTCEPSS rescore
- 2026-06-30 23:19 UTCEPSS rescore
- 2026-06-29 14:03 UTCEPSS rescore
- 2026-06-28 14:03 UTCEPSS rescore
- 2026-06-28 04:53 UTCEPSS rescore
- 2026-06-27 03:05 UTCEPSS rescore
- 2026-06-25 13:47 UTCEPSS rescore
- 2026-06-25 13:47 UTCEPSS rescore
- 2026-06-24 14:02 UTCEPSS rescore
- 2026-06-24 14:02 UTCEPSS rescore
- 2026-06-24 00:29 UTCOSV refresh
- 2026-06-23 21:30 UTCEPSS rescore
- 2026-06-22 14:23 UTCEPSS rescore
- 2026-06-22 14:22 UTCEPSS rescore
Show 43 moreShow fewer
- 2026-06-21 14:54 UTCEPSS rescore
- 2026-06-21 01:57 UTCEPSS rescore
- 2026-06-21 01:57 UTCEPSS rescore
- 2026-06-18 17:50 UTCEPSS rescore
- 2026-06-18 17:49 UTCEPSS rescore
- 2026-06-17 17:49 UTCEPSS rescore
- 2026-06-16 17:50 UTCEPSS rescore
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-15 17:45 UTCEPSS rescore
- 2026-06-14 23:14 UTCEPSS rescore
- 2026-06-13 22:57 UTCEPSS rescore
- 2026-06-12 23:09 UTCEPSS rescore
- 2026-06-11 13:57 UTCEPSS rescore
- 2026-06-10 22:15 UTCEPSS rescore
- 2026-06-08 14:14 UTCEPSS rescore
- 2026-06-07 15:22 UTCEPSS rescore
- 2026-06-07 06:55 UTCOSV refresh
- 2026-06-06 13:45 UTCEPSS rescore
- 2026-06-05 22:44 UTCEPSS rescore
- 2026-06-05 06:08 UTCEPSS rescore
- 2026-06-05 06:08 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 00:14 UTCEPSS rescore
- 2026-05-29 13:41 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-26 07:16 UTCEPSS rescore
- 2026-05-26 07:16 UTCEPSS rescore
- 2026-05-23 15:10 UTCEPSS rescore
- 2026-05-23 01:14 UTCEG score recompute
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 13:43 UTCOSV refresh
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-18 21:30 UTCEPSS rescore
- 2026-05-18 21:30 UTCEPSS rescore
Publicly available exploits
(1 reference)Working exploit code is in the public domain. Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.
- Nucleihttp/cves/2015/CVE-2015-4050.yamlFirst seen Jan 1, 2015
Symfony - Authentication Bypass
Open source ↗
Frequently asked(4)
What is CVE-2015-4050?
When was CVE-2015-4050 disclosed?
Is CVE-2015-4050 actively exploited?
How do I remediate CVE-2015-4050?
Dependency Blast Radius
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