What is the CVSS score of EUVD-2026-52445?

EUVD-2026-52445 has a CVSS 3.1 base score of 7.2 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N. EPSS exploitation probability: 0.2%.

Which versions of GuzzleHttp Guzzle are affected by EUVD-2026-52445?

GuzzleHttp Guzzle, a widely-used PHP HTTP client library, contains a host validation bypass (CVE-2026-69246, CVSS 7.2) that allows attackers to circumvent URL filtering safeguards and reach internal…. A patch is available.

Is there a public PoC exploit available for EUVD-2026-52445?

Yes, a public proof-of-concept exploit is available for EUVD-2026-52445. Prioritise patching immediately. EPSS: 0.2%.

How to fix or mitigate EUVD-2026-52445?

Within 24 hours, identify all systems using GuzzleHttp Guzzle versions before 7.15.2 or 8.0.1 and deploy network firewall rules blocking outbound connections from affected servers to internal IP ranges (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, 127.0.0.0/8) and loopback addresses. Within 7 days, assess each affected application's use of user-supplied URLs in HTTP requests to determine SSRF exposure; prioritize critical systems and implement compensating controls such as enhanced URL validation, strict allowlisting, or service isolation. Within 30 days, monitor GuzzleHttp security advisories for patch availability, prepare a deployment plan targeting versions 7.15.2 or 8.0.1, conduct staged testing in non-production environments, and coordinate organization-wide rollout with change management and validation.

GuzzleHttp Guzzle EUVD-2026-52445

| CVE-2026-69246 HIGH

Incorrect Behavior Order: Validate Before Canonicalize (CWE-180)

2026-08-03 GitHub_M

GHSA-v5mv-p594-2x33

PHP Information Disclosure Guzzle

7.2

CVSS 3.1 · Vendor: GitHub_M

Severity by source

Vendor (GitHub_M) PRIMARY

7.2 HIGH

AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

vuln.today AI

5.4 MEDIUM

AC:H reflects that exploitation requires the specific combination of untrusted URI input and host-based security controls; S:C retained because the vulnerability enables reaching and reading from out-of-scope internal hosts.

3.1 AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N

4.0 AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N

Primary rating from Vendor (GitHub_M).

CVSS VectorVendor: GitHub_M

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

Patch available

Aug 03, 2026 - 22:17 EUVD

Source Code Evidence Fetched

Aug 03, 2026 - 21:37 vuln.today

Analysis Generated

Aug 03, 2026 - 21:37 vuln.today

CVE Published

Aug 03, 2026 - 21:07 cve.org

HIGH 7.2

DescriptionCVE.org

Guzzle is an extensible PHP HTTP client. Prior to 7.15.2 and 8.0.1, Guzzle gives a transport the request URI as text and supplies the Host header separately. The cURL handlers set CURLOPT_URL to the URI exactly as written and push that Host into CURLOPT_HTTPHEADER; StreamHandler does the same through fopen(). libcurl then parses the authority itself, percent-decoding it and, on an IDN-capable build, applying IDNA mapping, and uses the result to resolve, connect, name the TLS peer and address a proxy CONNECT, while the supplied Host suppresses the aligned one libcurl would have generated. For a URI host written as 127.0.0.%31, filter_var() rejects the host as an IP literal, yet libcurl decodes it to 127.0.0.1 and reaches loopback with no DNS lookup while the server receives Host: 127.0.0.%31. An attacker who influences a fetched URI can therefore reach a host the application's checks excluded and read whatever the host exposes of the response. The same divergence moves Guzzle's own decisions onto a spelling the transport does not use: no_proxy selects proxy routing from the literal host, and RedirectMiddleware decides from it whether to strip Authorization and Cookie. Exploitation requires the application to build a request URI from untrusted input and to make a host decision before handing it to Guzzle. This issue is fixed in versions 7.15.2 and 8.0.1.

AnalysisAI

Host confusion in GuzzleHttp Guzzle before 7.15.2 and 8.0.1 allows remote attackers who can influence a fetched URI to bypass application-level host validation and reach network hosts the application intended to block, including loopback and internal addresses. The divergence occurs because PHP's filter_var() and Guzzle's own host checks operate on the literal URI text while libcurl independently percent-decodes and IDNA-maps the authority before resolving and connecting, meaning the application and transport disagree on which host is being contacted. No public exploit has been identified and the vulnerability is absent from the CISA KEV catalog, but any application that implements SSRF mitigations via URI host inspection before passing a user-supplied URL to Guzzle is directly undermined.

Technical ContextAI

GuzzleHttp Guzzle (CPE: cpe:2.3:a:guzzle:guzzle:*:*:*:*:*:*:*:*) is the dominant PHP HTTP client, used as a dependency by Laravel, Symfony, Drupal, and most major PHP frameworks. It delegates transport to libcurl via CurlHandler and CurlMultiHandler, or to PHP's stream wrappers via StreamHandler. The root cause is CWE-180 (Use of Incorrect Comparison): Guzzle passes the raw URI text to the transport while supplying the Host header separately. libcurl re-parses the URI authority independently, applying percent-decoding (e.g., %31 decodes to '1', making 127.0.0.%31 resolve as 127.0.0.1) and, on IDN-capable builds, IDNA mapping. PHP validators such as filter_var(FILTER_VALIDATE_IP) and Guzzle's own no_proxy matching, RedirectMiddleware auth/cookie-stripping logic, and cookie domain scoping all evaluate the literal URI string - a different value from what libcurl actually connects to. The fix introduces a HostValidator class that rejects percent-escaped URI hosts, non-printable ASCII in Host headers, authority delimiters in URI hosts, and numeric-looking hosts with trailing dots, and also regenerates the Host header after client URI rewrites to close the Host/URI divergence.

RemediationAI

Vendor-released patches are available: upgrade to GuzzleHttp Guzzle 7.15.2 or 8.0.1 via Composer using 'composer require guzzlehttp/guzzle:^7.15.2' or 'composer require guzzlehttp/guzzle:^8.0.1' respectively. Release notes and patch details are at https://github.com/guzzle/guzzle/releases/tag/7.15.2 and https://github.com/guzzle/guzzle/releases/tag/8.0.1. If immediate patching is not possible, applications can partially mitigate by resolving and normalizing all incoming URIs to their canonically decoded form before any host validation and before passing to Guzzle, ensuring the checked host matches the host libcurl will connect to; this requires decoding all percent-sequences and applying IDNA normalization, which is complex and error-prone. A simpler but stricter compensating control is to reject any URI whose host field contains a percent character ('%') or non-ASCII bytes before it reaches Guzzle, at the cost of blocking legitimate internationalized hostnames. Neither workaround addresses the third-party UriInterface userinfo attack surface. Patching is strongly preferred.