Symfony Session Fixation Vulnerability
A session fixation vulnerability within the "Remember Me" login feature allows an attacker to impersonate the victim towards the web application if the session id value was previously known to the attacker. This issue has been fixed in Symfony 2.3.35, 2.6.12, and 2.7.7. Note that no fixes are provided for Symfony 2.4 and 2.5 as they are not maintained anymore. Symfony 2.8 and 3.0 haven't been released yet and the fix will be included in their first stable releases.
Affected software
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| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Composer package | symfony/security | >= 2.3.0, < 2.3.35, >= 2.4.0, < 2.6.12, >= 2.7.0, < 2.7.7 | 2.3.35, 2.6.12, 2.7.7 |
| Composer package | symfony/security-http | >= 2.4.0, < 2.6.12, >= 2.7.0, < 2.7.7 | 2.6.12, 2.7.7 |
| Composer package | symfony/symfony | >= 2.3.0, < 2.3.35, >= 2.4.0, < 2.6.12, >= 2.7.0, < 2.7.7 | 2.3.35, 2.6.12, 2.7.7 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2015-8124
- https://github.com/symfony/symfony/pull/16631
- https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/security-http/CVE-2015-8124.yaml
- https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/security/CVE-2015-8124.yaml
- https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2015-8124.yaml
- https://symfony.com/blog/cve-2015-8124-session-fixation-in-the-remember-me-login-feature
- https://symfony.com/cve-2015-8124
- https://web.archive.org/web/20201209020014/http://www.securityfocus.com/archive/1/537183/100/0/threaded
- https://web.archive.org/web/20210125123853/http://www.securityfocus.com/bid/77694
- http://lists.fedoraproject.org/pipermail/package-announce/2015-December/173271.html
- http://lists.fedoraproject.org/pipermail/package-announce/2015-December/173300.html
- http://seclists.org/fulldisclosure/2015/Dec/89
- http://www.debian.org/security/2015/dsa-3402
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N- Weakness (CWE)
CWE-384- Platform
- Composer
- Package
symfony/security, symfony/security-http, symfony/symfony- Disclosed
- 14.05.2022
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-j5jh-hpr4-h332 - CC BY 4.0
Vulnerability history: symfony/security-http
All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 20
- First → latest
- 12.2019 06.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- High 10
- Medium 8
- Low 2
Disclosures per year
- 2019: 1
- 2020: 2
- 2021: 3
- 2022: 7
- 2023: 1
- 2024: 1
- 2025: 0
- 2026: 5
-
Symfony Session Fixation Vulnerability this entry
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