CVE-2020-24978

Name: CVE-2020-24978
Creator: NVD / NIST
Published: 2020-09-04T00:15:10.757+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 1.36%

Last modified Jun 17, 2026

CVE-2020-24978 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. In NASM 2.15.04rc3, there is a double-free vulnerability in pp_tokline asm/preproc.c. This is fixed in commit 8806c3ca007b84accac21dd88b900fb03614ceb7.. EPSS estimates a 1.36% chance of exploitation in the next 30 days.

Description

In NASM 2.15.04rc3, there is a double-free vulnerability in pp_tokline asm/preproc.c. This is fixed in commit 8806c3ca007b84accac21dd88b900fb03614ceb7.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

1.36%

68.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-415

Affected Software

Vendor	Product	Versions	Update
Nasm	Netwide Assembler	2.15.04	Rc3

References

https://bugzilla.nasm.us/show_bug.cgi?id=3392712Exploit, Issue Tracking, Vendor Advisory
https://bugzilla.nasm.us/show_bug.cgi?id=3392712Exploit, Issue Tracking, Vendor Advisory

Timeline

Published: Sep 4, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-24978?

In NASM 2.15.04rc3, there is a double-free vulnerability in pp_tokline asm/preproc.c. This is fixed in commit 8806c3ca007b84accac21dd88b900fb03614ceb7.

How severe is CVE-2020-24978?

CVE-2020-24978 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 1.36% probability of exploitation in the next 30 days.

How do I fix CVE-2020-24978?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-24978?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST