What is CVE-2015-8867?

CVE-2015-8867 is a high-severity vulnerability in PHP, classified under Cryptographic Issues. CVSS score: 7.5/10. Published 2016-05-22.

How severe is CVE-2015-8867?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2015-8867 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in PHP

CVE-2015-8867

The openssl_random_pseudo_bytes function in ext/openssl/openssl.c in PHP before 5.4.44, 5.5.x before 5.5.28, and 5.6.x before 5.6.12 incorrectly relies on the deprecated RAND_pseudo_bytes function, which makes it easier for remote attackers to defeat cryptographic protection mechanisms via unspecified vectors.

Vulnerability class: POODLE (CVE-2014-3566)

Published 2016-05-22 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.044 (90.9th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 91st percentile — 90.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.044 · newest: 0.044 · change: 0.000

Affected products

PHP
Canonical Ubuntu Linux — versions 12.04, 14.04, 15.10

Weakness classification (CWE)

CWE-310 — Cryptographic Issues

Public proof-of-concept exploits

References

www.ubuntu.com/usn/USN-2952-1 (vendor-advisory, Third Party Advisory)
www.php.net/ChangeLog-7.php (Vendor Advisory)
bugs.launchpad.net/ubuntu/+source/php5/+bug/1534203 (Third Party Advisory)
rhn.redhat.com/errata/RHSA-2016-2750.html (vendor-advisory, Third Party Advisory)
git.php.net/
www.ubuntu.com/usn/USN-2952-2 (vendor-advisory, Third Party Advisory)
bugs.php.net/bug.php (Vendor Advisory)
www.php.net/ChangeLog-5.php (Vendor Advisory)
lists.opensuse.org/opensuse-security-announce/2016-05/msg00031.html (vendor-advisory, Mailing List, Third Party Advisory)
lists.opensuse.org/opensuse-security-announce/2016-05/msg00033.html (vendor-advisory, Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2015-8867?: CVE-2015-8867 is a high-severity vulnerability in PHP, classified under Cryptographic Issues. CVSS score: 7.5/10. Published 2016-05-22.
How severe is CVE-2015-8867?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2015-8867 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.