CVE-2026-69246
CVE-2026-69246 — Guzzle: Noncanonical host can bypass host-based checks
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…
Published Updated Sources: cvelistV5, GitHub_M
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
chance of exploitation in 30 days
CVSS base
7.2
HIGH
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script all four kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 7.2 | CVSS 3.1 | HIGH | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-180
- CWE-436
- CWE-918
- CWE-941
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1027Obfuscated Files or Information
References
7 on the record
- github.com/guzzle/guzzle/security/advisories/GHSA-v5mv-p594-2x33
x_refsource_CONFIRM
- github.com/guzzle/guzzle/pull/3907
x_refsource_MISC
- github.com/guzzle/guzzle/pull/3908
x_refsource_MISC
- github.com/guzzle/guzzle/commit/3aeea0406aab88cbbd86531313d7cebf8ae149a4
x_refsource_MISC
- github.com/guzzle/guzzle/commit/744101956d78b7c1384d0cbf379db13e859167bf
x_refsource_MISC
- github.com/guzzle/guzzle/releases/tag/7.15.2
x_refsource_MISC
- github.com/guzzle/guzzle/releases/tag/8.0.1
x_refsource_MISC
Elsewhere on this site
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.