{"cve":"CVE-2015-6837","nvd":{"published":"2016-05-16T10:59:20.627","modified":"2026-06-17T00:31:30.510","status":"Modified","description":"The xsl_ext_function_php function in ext/xsl/xsltprocessor.c in PHP before 5.4.45, 5.5.x before 5.5.29, and 5.6.x before 5.6.13, when libxml2 before 2.9.2 is used, does not consider the possibility of a NULL valuePop return value before proceeding with a free operation during initial error checking, which allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via a crafted XML document, a different vulnerability than CVE-2015-6838.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":[],"references":["http://php.net/ChangeLog-5.php","http://www.debian.org/security/2015/dsa-3358","http://www.securityfocus.com/bid/76738","http://www.securitytracker.com/id/1033548","https://bugs.php.net/bug.php?id=69782"],"products":["php:php","xmlsoft:libxml2"],"source":"nvd","synced_at":"2026-10-19T20:38:51.654415212+00:00"},"epss":{"cve":"CVE-2015-6837","score":0.07349,"percentile":0.94401,"date":"2026-10-31"},"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."]}