Vulnerability in PHP
CVE-2015-6835
The session deserializer in PHP before 5.4.45, 5.5.x before 5.5.29, and 5.6.x before 5.6.13 mishandles multiple php_var_unserialize calls, which allow remote attackers to execute arbitrary code or cause a denial of service (use-after-free) via crafted session content.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.362 (98.4th percentile), scored .
Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 98th percentile — 98.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.370 · newest: 0.362 · change: -0.008
Affected products
- PHP — versions 5.6.0, 5.6.1, 5.6.2
Public proof-of-concept exploits
References
- www.securityfocus.com/bid/76734 (vdb-entry)
- bugs.php.net/bug.php
- www.securitytracker.com/id/1033548 (vdb-entry)
- php.net/ChangeLog-5.php
- www.debian.org/security/2015/dsa-3358 (vendor-advisory)
- security.gentoo.org/glsa/201606-10 (vendor-advisory)
Frequently asked questions
- What is CVE-2015-6835?
- CVE-2015-6835 is a critical-severity vulnerability in PHP. CVSS score: 9.8/10. Published 2016-05-16.
- How severe is CVE-2015-6835?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2015-6835 known to be exploited?
- 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.