CVE-2019-6291 — An issue was discovered in the function expr6 in eval

An issue was discovered in the function expr6 in eval.c in Netwide Assembler (NASM) through 2.14.02. There is a stack exhaustion problem caused by the expr6 function making recursive calls to itself in certain scenarios involving lots of '!' or '+' or '-&

01What is this vulnerability?

An issue was discovered in the function expr6 in eval.c in Netwide Assembler (NASM) through 2.14.02. There is a stack exhaustion problem caused by the expr6 function making recursive calls to itself in certain scenarios involving lots of '!' or '+' or '-' characters. Remote attackers could leverage this vulnerability to cause a denial-of-service via a crafted asm file.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2019-01-15T00:00:00.000Z
• Last modified: 2024-09-16T23:45:29.320Z

09References

• bugzilla.nasm.us — https://bugzilla.nasm.us/show_bug.cgi?id=3392549