VDB-160727 · CVE-2020-24979 · GCVE-0-2020-24979

GNU Bison 3.7.1.1-cb7dc-dirty src/symtab.c out-of-bounds write

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.
5.4	$0-$5k	0.00

Summaryinfo

A vulnerability was found in GNU Bison 3.7.1.1-cb7dc-dirty. It has been rated as critical. The affected element is an unknown function of the file src/symtab.c. The manipulation leads to out-of-bounds write. This vulnerability is uniquely identified as CVE-2020-24979. Local access is required to approach this attack. No exploit exists.

Detailsinfo

A vulnerability was found in GNU Bison 3.7.1.1-cb7dc-dirty and classified as critical. This issue affects an unknown function of the file src/symtab.c. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A Buffer Overflow vulnerability was found in src/symtab.c in GNU bison 3.7.1.1-cb7dc-dirty. A local attacker may execute bison with crafted input file redefining the EOF token, which could triggers Heap buffer overflow and thus cause system crash.

The weakness was disclosed 09/04/2020. The identification of this vulnerability is CVE-2020-24979 since 08/28/2020. Attacking locally is a requirement. The successful exploitation requires a simple authentication. Technical details of the vulnerability are known, but there is no available exploit.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The entry VDB-160728 is pretty similar. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Bison

Version

3.7.1.1-cb7dc-dirty

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: 5.4
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔍

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

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

08/28/2020 🔍
09/04/2020 +7 days 🔍
09/04/2020 +0 days 🔍
09/04/2020 +0 days 🔍

Sourcesinfo

Vendor: gnu.org

Status: Not defined

CVE: CVE-2020-24979 (🔍)
GCVE (CVE): GCVE-0-2020-24979
GCVE (VulDB): GCVE-100-160727
See also: 🔍

Entryinfo

Created: 09/04/2020 13:37
Updated: 09/04/2020 13:42
Changes: 09/04/2020 13:37 (36), 09/04/2020 13:42 (17)
Complete: 🔍
Cache ID: 216::103