Symfony Host Header Injection
An issue was discovered in HttpKernel in Symfony 2.7.0 through 2.7.48, 2.8.0 through 2.8.43, 3.3.0 through 3.3.17, 3.4.0 through 3.4.13, 4.0.0 through 4.0.13, and 4.1.0 through 4.1.2. When using HttpCache, the values of the X-Forwarded-Host headers are implicitly set as trusted while this should be forbidden, leading to potential host header injection.
Affected software
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| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Composer package | symfony/symfony | >= 2.7.0, < 2.7.49, >= 2.8.0, < 2.8.44, >= 3.3.0, < 3.3.18, >= 3.4.0, < 3.4.14, >= 4.0.0, < 4.0.14, >= 4.1.0, < 4.1.3 | 2.7.49, 2.8.44, 3.3.18, 3.4.14, 4.0.14, 4.1.3 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2018-14774
- https://github.com/symfony/symfony/commit/725dee4cd8b4ccd52e335ae4b4522242cea9bd4a
- https://github.com/symfony/symfony/commit/7f912bbb78377c2ea331b3da28363435fbd91337
- https://github.com/symfony/symfony/commit/96504fb8c9f91204727d2930eb837473ce154956
- https://github.com/symfony/symfony/commit/974240e178bb01d734bf1df1ad5c3beba6a2f982
- https://github.com/symfony/symfony/commit/9cfcaba0bf71f87683510b5f47ebaac5f5d6a5ba
- https://github.com/symfony/symfony/commit/bcf5897bb1a99d4acae8bf7b73e81bfdeaac0922
- https://github.com/symfony/symfony
- https://symfony.com/blog/cve-2018-14774-possible-host-header-injection-when-using-httpcache
- CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N- Weakness (CWE)
CWE-20- Platform
- Composer
- Package
symfony/symfony- Disclosed
- 14.05.2022
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-66p6-7p29-55p9 - CC BY 4.0
Vulnerability history: symfony/symfony
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
- 100
- First → latest
- 11.2019 06.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 8
- High 28
- Medium 51
- Low 13
Disclosures per year
- 2019: 6
- 2020: 7
- 2021: 6
- 2022: 29
- 2023: 5
- 2024: 16
- 2025: 1
- 2026: 30
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Symfony Host Header Injection this entry
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