October System module has a Reflected XSS via X-October-Request-Handler Header
Impact
The X-October-Request-Handler Header does not sanitize the AJAX handler name and allows unescaped HTML to be reflected back. There is no impact since this vulnerability cannot be exploited through normal browser interactions. This unescaped value is only detectable when using a proxy interception tool.
Patches
This issue has been patched in v3.5.15.
References
Credits to:
For more information
If you have any questions or comments about this advisory:
- Email us at hello@octobercms.com
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Composer package | october/system | >= 3.2, < 3.5.15 | 3.5.15 |
References
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N- Weakness (CWE)
CWE-79- Platform
- Composer
- Package
october/system- Disclosed
- 26.06.2024
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-rjw8-v7rr-r563 - CC BY 4.0
Vulnerability history: october/system
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
- 25
- First → latest
- 06.2020 09.2026
- Without a fix
- 0
- Exploited in attacks
- 1
Severity breakdown
- Critical 1
- High 8
- Medium 9
- Low 7
Disclosures per year
- 2020: 1
- 2021: 3
- 2022: 6
- 2023: 3
- 2024: 2
- 2025: 1
- 2026: 9
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October System module has a Reflected XSS via X-October-Request-Handler Header this entry
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