Bug 1824469 (CVE-2019-20334)

Summary:	CVE-2019-20334 nasm: stack consumption occurs in expr# functions in asm/eval.c
Product:	[Other] Security Response	Reporter:	Dhananjay Arunesh <darunesh>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	dominik, java-sig-commits, mizdebsk, nickc, pbonzini
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Fixed In Version:		Doc Type:	If docs needed, set a value
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Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1824470, 1824813, 1824814
Bug Blocks:	1824471

Description Dhananjay Arunesh 2020-04-16 09:40:25 UTC

In Netwide Assembler (NASM) 2.14.02, stack consumption occurs in expr# functions in asm/eval.c. This potentially affects the relationships among expr0, expr1, expr2, expr3, expr4, expr5, and expr6 (and stdscan in asm/stdscan.c). This is similar to CVE-2019-6290 and CVE-2019-6291.

https://bugzilla.nasm.us/show_bug.cgi?id=3392548#c4
https://bugzilla.nasm.us/show_bug.cgi?id=3392638

Comment 1 Dhananjay Arunesh 2020-04-16 09:40:50 UTC

Created nasm tracking bugs for this issue:

Affects: fedora-all [bug 1824470]

Comment 2 Stefan Cornelius 2020-04-16 13:50:39 UTC

This only works for me when arbitrarily limiting the stack space via ulimit. This has a CVE and technically we're affected, but overall the impact is so low that it hardly seems relevant.