{"cve":"CVE-2023-29197","nvd":{"published":"2023-04-17T22:15:09.947","modified":"2026-06-17T05:49:35.320","status":"Modified","description":"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 incomplete. The issue has been patched in versions 1.9.1 and 2.4.5. There are no known workarounds for this vulnerability. Users are advised to upgrade.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","score":7.5},"cwes":["CWE-436"],"references":["https://cve.mitre.org/cgi-bin/cvename.cgi?name=2022-24775","https://github.com/guzzle/psr7/security/advisories/GHSA-q7rv-6hp3-vh96","https://github.com/guzzle/psr7/security/advisories/GHSA-wxmh-65f7-jcvw","https://lists.debian.org/debian-lts-announce/2023/12/msg00028.html","https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FJANWDXJZE5BGLN4MQ4FEHV5LJ6CMKQF/"],"products":["fedoraproject:fedora","guzzlephp:psr-7"],"source":"nvd","synced_at":"2026-10-19T21:38:05.473481323+00:00"},"epss":{"cve":"CVE-2023-29197","score":0.01216,"percentile":0.68586,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}