CVE-2018-20535: nasm netwide_assembler Use After Free
CVSS: 5.5v3.0MediumModified
AliasesUBUNTU-CVE-2018-20535DEBIAN-CVE-2018-20535
Published 28-12-2018Last modified 05-08-2024
Vulnerability summary
CVE-2018-20535 is a medium (CVSS 5.5) Use After Free vulnerability in nasm netwide_assembler. EPSS estimates a 0.80% chance of exploitation in the next 30 days, higher than 55.6% of scored vulnerabilities. 1 public exploit is recorded.
CVSS score
5.5/10
010
Medium · v3.0 (NVD)EPSS score
0.80%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference
Timeline
- 28-12-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
There is a use-after-free at asm/preproc.c (function pp_getline) in Netwide Assembler (NASM) 2.14rc16 that will cause a denial of service during a line-number increment attempt.
CVSS metrics
4 scores · 3 sources · 2 versionsMedium 5.5Preferred score · NVD (NIST)
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Medium 4.3Preferred score · NVD (NIST)
AV:N/AC:M/Au:N/C:N/I:N/A:PSourcesSingle source
EPSS trend
Probability
0.80%
Chance of exploitation in the next 30 days
Percentile
56%
Versus all other CVEs
30-day change
0.00 pp
From 0.80% on 19-09-2026
19-09-202619-10-2026
EPSS score0.80%
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_assembler2.14.0:rc16
Ubuntu1 product
- nasmAll versions (No fix recorded)
3 vendors · 3 products
