CVE Vulnerability

CVE-2020-24240

GNU Bison before 3.7.1 has a use-after-free in _obstack_free in lib/obstack.c (called from gram_lex) when a '' byte is encountered. NOTE: there is a risk only if Bison is used with untrusted input, and the observed bug happens to cause unsafe behavior with a specific compiler/architecture. The bug report was intended to show that a crash may occur in Bison itself, not that a crash may occur in code that is generated by Bison.

7.1 /10

CVSS v2.0 :

V3 Legend

Vector :

Exploitability : 8.6 / Impact : 6.9

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact COMPLETE

Scope

5.5 /10

CVSS v3.0 : MEDIUM

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://github.com/akimd/bison/commit/be95a4fe2951374676efc9454ffee8638faaf68d Patch Third Party Advisory
https://lists.gnu.org/r/bug-bison/2020-07/msg00051.html Mailing List Vendor Advisory
https://github.com/akimd/bison/compare/v3.7...v3.7.1 Third Party Advisory
Configurations

Configuration 1

cpe:2.3:a:gnu:bison:3.7:*:*:*:*:*:*:*
Information

Published : 2020-08-25 02:15

Updated : 2020-09-02 02:31

NVD link : CVE-2020-24240

Mitre link : CVE-2020-24240

Products Affected

Bison

Gnu

CWE
CWE-416