CVE-2023-29197: Improper header name validation in guzzlehttp/psr7

medium Affects guzzlehttp/psr7. Feed 2026.10.29.1, updated 2026-10-28; published 2023-04-19; advisory modified 2026-02-04.

Improper header name validation in guzzlehttp/psr7

Package: guzzlehttp/psr7 Composer
Affected versions: <1.9.1 or >=2.0.0 and <2.4.5 or >=2 and <2.4.5
Fixed in: 1.9.1, 2.4.5
Severity: medium CVSS 5.3
Exploitation: not on CISA KEV · EPSS 1% (68.5th percentile)
Published: 2023-04-19
Source: osv.dev

References

CWE-436

NVD record guzzlehttp/psr7 advisories

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Related advisories

CVE-2022-24775 medium Improper Input Validation in guzzlehttp/psr7 same package: guzzlehttp/psr7
CVE-2026-59882 medium guzzlehttp/psr7: Host Confusion via Weak URI Host Validation same package: guzzlehttp/psr7
CVE-2026-55766 medium guzzlehttp/psr7: CRLF Injection in HTTP Start-Line Serialization same package: guzzlehttp/psr7
CVE-2026-48998 medium guzzlehttp/psr7 has Host Confusion via Authority Reinterpretation same package: guzzlehttp/psr7
CVE-2026-49214 medium guzzlehttp/psr7 has CRLF Injection via URI Host Component same package: guzzlehttp/psr7
CVE-2026-63030 KEV critical WordPress 6.9.x before 6.9.5 and 7.0.x before 7.0.2 is affected by a REST API batch endpoi same weakness: CWE-436