What is CVE-2016-9935?

CVE-2016-9935 is a critical-severity vulnerability in PHP, classified under Out-of-bounds Read. CVSS score: 9.8/10. Published 2017-01-04.

How severe is CVE-2016-9935?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2016-9935 known to be exploited?

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

Out-of-bounds Read in PHP

CVE-2016-9935

The php_wddx_push_element function in ext/wddx/wddx.c in PHP before 5.6.29 and 7.x before 7.0.14 allows remote attackers to cause a denial of service (out-of-bounds read and memory corruption) or possibly have unspecified other impact via an empty boolean element in a wddxPacket XML document.

Vulnerability class: Buffer Overflow

Published 2017-01-04 · last modified 2026-06-17.

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: 0.070 (94.0th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 94th percentile — 94.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.070 · newest: 0.070 · change: 0.000

Affected products

PHP — versions 7.0.0, 7.0.1, 7.0.2

Weakness classification (CWE)

CWE-125 — Out-of-bounds Read

Public proof-of-concept exploits

References

github.com/php/php-src/commit/66fd44209d5ffcb9b3d1bc1b9fd8e35b485040c0 (Patch, Vendor Advisory)
www.openwall.com/lists/oss-security/2016/12/12/2 (mailing-list, Third Party Advisory)
www.debian.org/security/2016/dsa-3737 (vendor-advisory)
lists.opensuse.org/opensuse-updates/2017-01/msg00054.html (vendor-advisory)
www.php.net/ChangeLog-7.php (Release Notes, Vendor Advisory)
access.redhat.com/errata/RHSA-2018:1296 (vendor-advisory)
www.php.net/ChangeLog-5.php (Release Notes, Vendor Advisory)
lists.opensuse.org/opensuse-updates/2017-01/msg00034.html (vendor-advisory)
lists.opensuse.org/opensuse-updates/2016-12/msg00142.html (vendor-advisory)
bugs.php.net/bug.php (Vendor Advisory)

Frequently asked questions

What is CVE-2016-9935?: CVE-2016-9935 is a critical-severity vulnerability in PHP, classified under Out-of-bounds Read. CVSS score: 9.8/10. Published 2017-01-04.
How severe is CVE-2016-9935?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2016-9935 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.