Bug 1214531 (CVE-2020-21686) - VUL-0: CVE-2020-21686: nasm: stack-use-after-scope issue in expand_mmac_params function in preproc.c
Summary: VUL-0: CVE-2020-21686: nasm: stack-use-after-scope issue in expand_mmac_param...
Status: RESOLVED WONTFIX
Alias: CVE-2020-21686
Product: SUSE Security Incidents
Classification: Novell Products
Component: Incidents (show other bugs)
Version: unspecified
Hardware: Other Other
: P3 - Medium : Minor
Target Milestone: ---
Assignee: Security Team bot
QA Contact: Security Team bot
URL: https://smash.suse.de/issue/375968/
Whiteboard: CVSSv3.1:SUSE:CVE-2020-21686:3.3:(AV:...
Keywords:
Depends on:
Blocks:
 
Reported: 2023-08-23 13:39 UTC by Alexander Bergmann
Modified: 2024-04-19 08:59 UTC (History)
5 users (show)

See Also:
Found By: Security Response Team
Services Priority:
Business Priority:
Blocker: ---
Marketing QA Status: ---
IT Deployment: ---

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Description Alexander Bergmann 2023-08-23 13:39:49 UTC 
CVE-2020-21686

A stack-use-after-scope issue discovered in expand_mmac_params function in
preproc.c in nasm before 2.15.04 allows remote attackers to cause a denial of
service via crafted asm file.

No upstream fix available.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2020-21686
https://www.cve.org/CVERecord?id=CVE-2020-21686
https://bugzilla.nasm.us/show_bug.cgi?id=3392643
Comment 1 Alexander Bergmann 2023-08-23 13:40:42 UTC 
https://bugzilla.nasm.us/show_bug.cgi?id=3392643#c1

Doesn't trigger in nasm-2.15.04rc5-4-g51e23ac7

So it looks like the only affected code-streams are:

SUSE:SLE-12:Update
SUSE:SLE-15:Update
Comment 2 Alexander Bergmann 2023-08-23 13:40:47 UTC 
Note: Do not trust data from unknown sources. Do not assemble/disassemble binaries from unknown sources without a sandbox environment that protects you from possible attacks.

In general: This is not a severe issue. It can only be exploited if general security measurements and best practices are not followed.
Comment 4 Michael Vetter 2023-09-20 08:07:38 UTC 
Please see https://bugzilla.suse.com/show_bug.cgi?id=1214499#c4
Comment 5 Carlos López 2024-04-19 08:59:39 UTC 
Closing as WONTFIX as discussed above.