Server-side Request Forgery (SSRF) Affecting guzzlehttp/psr7 package, versions <2.10.2
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-PHP-GUZZLEHTTPPSR7-17318033
- published12 Jun 2026
- disclosed11 Jun 2026
- creditVolker Dusch
Introduced: 11 Jun 2026
NewCVE-2026-48998 (opens in a new tab)How to fix?
Upgrade guzzlehttp/psr7 to version 2.10.2 or higher.
Overview
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via improper validation of the Host header when parsing raw HTTP request messages or deriving a server request URI from server variables. An attacker can manipulate the Host header to include URI authority delimiters, causing the constructed URI host to differ from the original value, potentially resulting in requests or credentials being sent to an unintended host by exploiting affected forwarding or gateway scenarios.
Workaround
This vulnerability can be mitigated by validating the Host header as uri-host [ ":" port ] before calling Message::parseRequest() or legacy parse_request() on untrusted HTTP request data, or before deriving routing and forwarding decisions from a parsed request URI. Reject Host values containing userinfo (@), path (/ or \), query (?), fragment (#) delimiters.