CVE-2020-24240

CVSS V2 High 7.1 CVSS V3 Medium 5.5
Description
GNU Bison before 3.7.1 has a use-after-free in _obstack_free in lib/obstack.c (called from gram_lex) when a '\0' 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.
Overview
  • CVE ID
  • CVE-2020-24240
  • Assigner
  • cve@mitre.org
  • Vulnerability Status
  • Analyzed
  • Published Version
  • 2020-08-25T14:15:16
  • Last Modified Date
  • 2020-09-02T14:31:13
Weakness Enumerations
CWE URL
CWE-416 http://cwe.mitre.org/data/definitions/416.html
CPE Configuration (Product)
CPE Vulnerable Operator Version Start Version End
cpe:2.3:a:gnu:bison:3.7:*:*:*:*:*:*:* 1 OR
CVSS Version 2
  • Version
  • 2.0
  • Vector String
  • AV:N/AC:M/Au:N/C:N/I:N/A:C
  • Access Vector
  • NETWORK
  • Access Compatibility
  • MEDIUM
  • Authentication
  • NONE
  • Confidentiality Impact
  • NONE
  • Integrity Impact
  • NONE
  • Availability Impact
  • COMPLETE
  • Base Score
  • 7.1
  • Severity
  • HIGH
  • Exploitability Score
  • 8.6
  • Impact Score
  • 6.9
CVSS Version 3
  • Version
  • 3.1
  • Vector String
  • CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
  • Attack Vector
  • LOCAL
  • Attack Compatibility
  • LOW
  • Privileges Required
  • NONE
  • User Interaction
  • REQUIRED
  • Scope
  • UNCHANGED
  • Confidentiality Impact
  • NONE
  • Availability Impact
  • HIGH
  • Base Score
  • 5.5
  • Base Severity
  • MEDIUM
  • Exploitability Score
  • 1.8
  • Impact Score
  • 3.6
References
Reference URL Reference Tags
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
Sources
Source Name Source URL
NIST https://nvd.nist.gov/vuln/detail/CVE-2020-24240
MITRE https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-24240
History
Created Old Value New Value Data Type Notes
2022-05-10 16:27:19 Added to TrackCVE
2022-12-04 21:28:50 2020-08-25T14:15Z 2020-08-25T14:15:16 CVE Published Date updated
2022-12-04 21:28:50 2020-09-02T14:31:13 CVE Modified Date updated
2022-12-04 21:28:50 Analyzed Vulnerability Status updated