CVE-2020-21687: nasm netwide_assembler Out-of-bounds Write
CVSS: 5.5v3.1MediumModified
AliasesUBUNTU-CVE-2020-21687DEBIAN-CVE-2020-21687
Published 22-08-2023Last modified 03-10-2024
Vulnerability summary
CVE-2020-21687 is a medium (CVSS 5.5) Out-of-bounds Write vulnerability in nasm netwide_assembler. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 36.8% of scored vulnerabilities. 1 public exploit is recorded.
CVSS score
5.5/10
010
Medium · v3.1 (NVD)EPSS score
0.44%
0%100%
Low · -0.01 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference
Timeline
- 22-08-2023PublishedVulnerability first disclosed.
- 03-10-2024Last modifiedVulnerability information updated.
Description
Buffer Overflow vulnerability in scan function in stdscan.c in nasm 2.15rc0 allows remote attackers to cause a denial of service via crafted asm file.
CVSS metrics
3 scores · 3 sources · 1 versionMedium 5.5Preferred score · NVD (NIST)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.44%
Chance of exploitation in the next 30 days
Percentile
37%
Versus all other CVEs
30-day change
-0.01 pp
From 0.44% on 20-09-2026
20-09-202620-10-2026
EPSS score0.44%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundExploit Reference (bugzilla.nasm.us)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Debian1 product
- nasm< 2.15.04-1
Nasm1 product
- netwide_assembler2.15:rc0
Ubuntu1 product
- nasmAll versions (No fix recorded)
3 vendors · 3 products
