CVE-2016-4071PHP Vulnerability
php: Format string vulnerability in php_snmp_error()
Published Mar 2, 2016 · Updated Aug 7, 2026 · Also known as UBUNTU-CVE-2016-4071
Key Facts
Patch immediately- CVE-2016-4071 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting PHP, Mac OS X (Apple), php5 (debian) and 22 more products.
- It is not listed in any known-exploited vulnerabilities catalog. A public exploit is reported by tracking sources, but no code link is listed yet.
- EPSS estimates a 20% probability of exploitation in the next 30 days.
- Fixed versions are available, including apache2-mod_php5 5.5.14-47.1, apache2-mod_php5 5.5.14-56.1, apache2-mod_php5 5.6.1-57.1.
- Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
Scores
CVSS v3.1
9.8
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
20%
Higher than 97.4% of all scored CVEs
Exploit maturity
Proof of concept
ATLAS score
43/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Not listed
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Proof of concept
Public exploit code
1
Proof-of-concept links
In-the-wild evidence
1
Reports of active use
Advisories And Exploit References
Description
Format string vulnerability in the php_snmp_error function in ext/snmp/snmp.c in PHP before 5.5.34, 5.6.x before 5.6.20, and 7.x before 7.0.5 allows remote attackers to execute arbitrary code via format string specifiers in an SNMP::get call.
Affected Products
380 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| PHPPHP | 5.5.0, 5.5.0-alpha1, 5.5.0-alpha2, 5.5.0-alpha3, 5.5.0-alpha4, 5.5.0-alpha5, 5.5.0-alpha6, 5.5.0-beta1 | n/a |
| Mac OS XApple | See advisory | 10.11.4 |
| php5debian | See advisory | 5.4.45-0+deb7u3 |
| php7.0ubuntu | See advisory | 7.0.4-7ubuntu2.1 |
| php55-bcmathamazon | See advisory | 5.5.35-1.114.amzn1 |
Patched Releases
apache2-mod_php5
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
apache2-mod_php5-debuginfo
5.6.1-57.1
Mac OS X
10.11.4
php5
5.4.45-0+deb7u3, 5.5.14-47.1, 5.5.14-56.1, 5.5.9+dfsg-1ubuntu4.16, 5.5.9+dfsg-1ubuntu4.17, 5.6.1-57.1, 5.6.20+dfsg-0+deb8u1
php5-bcmath
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-bcmath-debuginfo
5.6.1-57.1
php5-bz2
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-bz2-debuginfo
5.6.1-57.1
php5-calendar
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-calendar-debuginfo
5.6.1-57.1
php5-ctype
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-ctype-debuginfo
5.6.1-57.1
php5-curl
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-curl-debuginfo
5.6.1-57.1
php5-dba
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-dba-debuginfo
5.6.1-57.1
php5-debuginfo
5.6.1-57.1
php5-debugsource
5.6.1-57.1
php5-devel
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-dom
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-dom-debuginfo
5.6.1-57.1
php5-enchant
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-enchant-debuginfo
5.6.1-57.1
php5-exif
5.5.14-47.1, 5.5.14-56.1, 5.6.1-57.1
php5-exif-debuginfo
5.6.1-57.1
Timeline
Publicly disclosed
Mar 2, 2016
Last updated
Aug 7, 2026
Weakness Type
- CWE-20 Improper Input Validation
- CWE-134 Use of Externally-Controlled Format String
References
- advisoryubuntu.com · CVE-2016-4071
- advisorycve.org · CVERecord
- advisoryRHSA-2016:2750
- advisorybugzilla.suse.com · 976996
- advisorybugzilla.suse.com · 976997
FAQ
Common Questions.
Format string vulnerability in the php_snmp_error function in ext/snmp/snmp.c in PHP before 5.5.34, 5.6.x before 5.6.20, and 7.x before 7.0.5 allows remote attackers to execute arbitrary code via format string specifiers in an SNMP::get call.
Affected: PHP versions 5.5.0, 5.5.0-alpha1, 5.5.0-alpha2, 5.5.0-alpha3, 5.5.0-alpha4, 5.5.0-alpha5, 5.5.0-alpha6, 5.5.0-beta1; Mac OS X (Apple); php5 (debian), among others. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
A public exploit is reported by tracking sources, but no code link is listed yet.
Fixed versions are available, including apache2-mod_php5 5.5.14-47.1, apache2-mod_php5 5.5.14-56.1, apache2-mod_php5 5.6.1-57.1.
Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
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