Facebook HHVM up to 3.14.x StringUtil::implode integer overflow

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
8.4	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Facebook HHVM up to 3.14.x. This impacts the function StringUtil::implode. Such manipulation leads to integer overflow. This vulnerability is documented as CVE-2016-6872. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Facebook HHVM up to 3.14.x (Social Network Software) and classified as critical. Affected by this issue is the function StringUtil::implode. The manipulation with an unknown input leads to a integer overflow vulnerability. Using CWE to declare the problem leads to CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Integer overflow in StringUtil::implode in Facebook HHVM before 3.15.0 allows attackers to have unspecified impact via unknown vectors.

The bug was discovered 08/11/2016. The weakness was released 02/17/2017 (oss-sec). The advisory is available at openwall.com. This vulnerability is handled as CVE-2016-6872 since 08/18/2016. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit.

The vulnerability was handled as a non-public zero-day exploit for at least 190 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 264209 (Linux Distros Unpatched Vulnerability : CVE-2016-6872), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.15.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (264209). Entries connected to this vulnerability are available at VDB-97104, VDB-97105, VDB-97107 and VDB-97108. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Social Network Software

Name

• Facebook HHVM

Version

• 3.0
• 3.1
• 3.2
• 3.3
• 3.4
• 3.5
• 3.6
• 3.7
• 3.8
• 3.9
• 3.10
• 3.11
• 3.12
• 3.13
• 3.14

License

• free

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 264209
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2016-6872

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Facebook HHVM 3.15.0

Timelineinfo

08/11/2016 🔍
08/18/2016 +7 days 🔍
02/17/2017 +183 days 🔍
02/17/2017 +0 days 🔍
02/18/2017 +1 days 🔍
09/13/2025 +3129 days 🔍

Sourcesinfo

Advisory: openwall.com
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-6872 (🔍)
GCVE (CVE): GCVE-0-2016-6872
GCVE (VulDB): GCVE-100-97106
OSVDB: - CVE-2016-6872 - Facebook - HHVM - Integer Overflow Issue

See also: 🔍

Entryinfo

Created: 02/18/2017 08:59
Updated: 09/13/2025 23:45
Changes: 02/18/2017 08:59 (61), 08/15/2020 18:23 (2), 09/13/2025 23:45 (20)
Complete: 🔍
Cache ID: 216:1AE:103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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