When a stream context uses an HTTP proxy with request_fulluri enabled, the URI is not checked for CR/LF characters, allowing request smuggling or arbitrary requests through the proxy.
Affected versions
| Branch | Affected | Fixed in |
|---|---|---|
| PHP 8.3 | < 8.3.14 | 8.3.14 |
| PHP 8.2 | < 8.2.26 | 8.2.26 |
| PHP 8.1 | < 8.1.31 | 8.1.31 |
Older branches: not assessed
Exploitation conditions
- Stream context configured with a proxy and request_fulluri
Remediation
Upgrade to 8.1.31, 8.2.26, 8.3.14 or a later release of your branch. If your branch is end-of-life, move to a supported branch. Distribution packages may carry a backported fix under an older version number; confirm with your vendor's security tracker.
A version number alone cannot prove patch status. Linux distributions and hosting providers often backport security fixes without changing the version. Check your vendor’s changelog.
Severity scores
| CVSS | Source | Vector |
|---|---|---|
| 7.2 v3.0 | CNA | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
References
Data provenance
Secondary sources · pending primary verificationLast reviewed: Oct 24, 2026 · Source