GNU C Library up to 2.21 libio/wstrops.c IO_wstr_overflow 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.
7.3	$0-$5k	0.00

Summaryinfo

A vulnerability described as critical has been identified in GNU C Library up to 2.21. The impacted element is the function IO_wstr_overflow of the file libio/wstrops.c. The manipulation results in integer overflow. This vulnerability is reported as CVE-2015-8983. The attack can be launched remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, was found in GNU C Library up to 2.21 (Software Library). Affected is the function IO_wstr_overflow of the file libio/wstrops.c. The manipulation with an unknown input leads to a integer overflow vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Integer overflow in the _IO_wstr_overflow function in libio/wstrops.c in the GNU C Library (aka glibc or libc6) before 2.22 allows context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via vectors related to computing a size in bytes, which triggers a heap-based buffer overflow.

The bug was discovered 08/14/2014. The weakness was disclosed 03/20/2017 by Joseph Myers (Website). The advisory is shared for download at sourceware.org. This vulnerability is traded as CVE-2015-8983 since 02/14/2017. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 949 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 97856 (Ubuntu 12.04 LTS / 14.04 LTS / 16.04 LTS : eglibc, glibc vulnerabilities (USN-3239-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196734 (Ubuntu Security Notification for Eglibc, Glibc Vulnerabilities (USN-3239-1)).

Upgrading to version 2.22 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (97856) and SecurityFocus (BID 72740†). The entries VDB-90572, VDB-92506, VDB-98122 and VDB-98293 are pretty similar. Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Software Library

Vendor

• GNU

Name

• C Library

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21

License

• open-source

Website

• Vendor: https://www.gnu.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.7
VulDB Meta Temp Score: 7.5

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

NVD Base Score: 8.1
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: 97856
Nessus Name: Ubuntu 12.04 LTS / 14.04 LTS / 16.04 LTS : eglibc, glibc vulnerabilities (USN-3239-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 841810
OpenVAS Name: Ubuntu Update for eglibc USN-3239-3
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: C Library 2.22

Timelineinfo

08/14/2014 🔍
02/22/2015 +192 days 🔍
02/14/2017 +723 days 🔍
03/20/2017 +34 days 🔍
03/20/2017 +0 days 🔍
03/20/2017 +0 days 🔍
03/21/2017 +1 days 🔍
03/21/2017 +0 days 🔍
09/10/2020 +1269 days 🔍

Sourcesinfo

Vendor: gnu.org

Advisory: sourceware.org
Researcher: Joseph Myers
Status: Not defined
Confirmation: 🔍

CVE: CVE-2015-8983 (🔍)
GCVE (CVE): GCVE-0-2015-8983
GCVE (VulDB): GCVE-100-98292
SecurityFocus: 72740 - GNU glibc 'libio/wstrops.c' Local Integer Overflow Vulnerability
OSVDB: - CVE-2015-8983 - GNU - C Library - Integer Overflow Issue

See also: 🔍

Entryinfo

Created: 03/21/2017 07:46
Updated: 09/10/2020 10:31
Changes: 03/21/2017 07:46 (80), 09/10/2020 10:31 (3)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

Discussion

Want to stay up to date on a daily basis?

Enable the mail alert feature now!