SARA / Free Tools / CVE / CVE-2023-29197

CVE-2023-29197 — guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Affected versions are subject to improper header parsing. An attacker could sneak in a newline (\n) into both the header names and values. While the specification states that \r\n\r\n is used to terminate the

CVSS
5.3 MEDIUM
EPSS
4.49% (top 11.00%)
CWE
CWE-436
Published
2023-04-17T21:08:46.675Z
Last modified
2025-02-13T16:49:01.562Z
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

01What is this vulnerability?

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Affected versions are subject to improper header parsing. An attacker could sneak in a newline (\n) into both the header names and values. While the specification states that \r\n\r\n is used to terminate the header list, many servers in the wild will also accept \n\n. This is a follow-up to CVE-2022-24775 where the fix was…

02Affected products

VendorProductVersions
guzzlepsr7< 1.9.1, >= 2.0.0, < 2.4.5

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

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07Related CVEs

CVE-2022-24775
Cited in vendor advisory

08Timeline

09References

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