guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Versions prior to 2.10.2 did not reject ASCII control characters, whitespace, or DEL in first-party URI host components. A vulnerable flow is: First, an application accepts a user-controlled URL. Second, the URL is used to construct a PSR-7 `Uri` or `Request`. Third, the host component contains CRLF or another header-unsafe character. Fourth, the host is copied into the PSR-7 `Host` header when no explicit `Host` header is provided. Finally, the request is serialized or sent by an HTTP client that does not independently reject the malformed host. In that flow, an attacker can cause the serialized request to contain additional attacker-controlled header lines. For example, a host containing `"\r\nX-Injected: yes"` can cause the generated `Host` header to span multiple HTTP header lines. Applications are affected when they use user-controlled URLs for outbound HTTP requests, URL forwarding, proxying, crawling, webhook delivery, or similar request-dispatch flows. In deployments involving HTTP/1.1 connection reuse, proxies, gateways, or load balancers, this malformed request may also contribute to request smuggling or cache poisoning, depending on how downstream components parse the request. The issue is patched in `2.10.2` and later. `1.x` is end-of-life and will not receive a patch. As a workaround, validate and reject all untrusted URI strings before constructing PSR-7 `Uri` or `Request` instances. Reject input containing ASCII control characters, whitespace, or DEL, including CRLF, tab, space, NUL, or DEL characters. Applications that forward requests should also ensure the final HTTP client or serializer rejects invalid URI and header data before writing requests to the network.
References
| Link | Resource |
|---|---|
| https://github.com/guzzle/psr7/security/advisories/GHSA-hq7v-mx3g-29hw | Mitigation Vendor Advisory |
Configurations
History
15 Jun 2026, 14:41
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:a:guzzlephp:psr-7:*:*:*:*:*:*:*:* | |
| First Time |
Guzzlephp psr-7
Guzzlephp |
|
| References | () https://github.com/guzzle/psr7/security/advisories/GHSA-hq7v-mx3g-29hw - Mitigation, Vendor Advisory |
11 Jun 2026, 13:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-06-11 13:16
Updated : 2026-06-15 14:41
NVD link : CVE-2026-49214
Mitre link : CVE-2026-49214
CVE.ORG link : CVE-2026-49214
JSON object : View
Products Affected
guzzlephp
- psr-7
