Bug 1877772 (CVE-2020-24979)

Summary:	CVE-2020-24979 bison: Buffer overflow in src/symtab.c via crafted input file redefining the EOF token can lead to DoS
Product:	[Other] Security Response	Reporter:	Michael Kaplan <mkaplan>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	arjun.is, ashankar, emachado, me, pfrankli
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-11-02 17:46:42 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1877776, 1882044, 1882045
Bug Blocks:	1877775

Description Michael Kaplan 2020-09-10 12:18:40 UTC

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.

References:

https://github.com/akimd/bison/commit/bfd851e2d621734886c66c0af26e861e718510b2
https://lists.gnu.org/r/bug-bison/2020-08/msg00008.html

Comment 1 Michael Kaplan 2020-09-10 12:20:04 UTC

Created bison tracking bugs for this issue:

Affects: fedora-all [bug 1877776]

Comment 6 Todd Cullum 2020-09-23 16:55:33 UTC

Mitigation:

This flaw can be mitigated by not supplying untrusted input to be processed by GNU Bison.

Comment 7 Red Hat Bugzilla 2023-09-15 00:47:51 UTC

The needinfo request[s] on this closed bug have been removed as they have been unresolved for 500 days