Use After Free in PHP

CVE-2016-6290

ext/session/session.c in PHP before 5.5.38, 5.6.x before 5.6.24, and 7.x before 7.0.9 does not properly maintain a certain hash data structure, which allows remote attackers to cause a denial of service (use-after-free) or possibly have unspecified other impact via vectors related to session deserialization.

Vulnerability class: Use-After-Free

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: 0.055 (92.5th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 92nd percentile — 92.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2016-6290: held from 0.055 to 0.055.

EPSS over last 30 days · oldest: 0.055 · newest: 0.055 · change: 0.000

Affected products

  • PHP — versions 5.6.0, 5.6.1, 5.6.2

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2016-6290?
CVE-2016-6290 is a critical-severity vulnerability in PHP, classified under Use After Free. CVSS score: 9.8/10. Published 2016-07-25.
How severe is CVE-2016-6290?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2016-6290 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.