CVE-2026-76921: wireshark foundation wireshark Use After Free
CVSS: 5.5v3.1MediumAnalyzed
AliasesUBUNTU-CVE-2026-76921DEBIAN-CVE-2026-76921
Published 19-08-2026Last modified 20-08-2026
Vulnerability summary
CVE-2026-76921 is a medium (CVSS 5.5) Use After Free vulnerability in wireshark foundation wireshark. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 4.2% of scored vulnerabilities. 2 public exploits are recorded.
CVSS score
5.5/10
010
Medium · v3.1 (CVE.org)EPSS score
0.15%
0%100%
Low · +0.04 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits2reference
Advisory lineage
Upstream 0 · Downstream 4 · Related 4Timeline
- 19-08-2026PublishedVulnerability first disclosed.
- 20-08-2026Last modifiedVulnerability information updated.
Description
CMS protocol dissector crash in 4.6.0 to 4.6.7 and 4.4.0 to 4.4.18 allows denial of service
CVSS metrics
4 scores · 4 sources · 1 versionMedium 5.5Preferred score · CVE.org (CNA)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:HSourcesAll 4 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
- NVDNIST5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.15%
Chance of exploitation in the next 30 days
Percentile
4%
Versus all other CVEs
30-day change
+0.04 pp
From 0.11% on 18-09-2026
18-09-202618-10-2026
EPSS score0.15%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
2 foundExploit Reference (gitlab.com)
Maturity: unknown
Exploit Reference (gitlab.com)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Debian1 product
- wiresharkAll versions (No fix recorded) | < 4.4.18-0+deb13u1 | < 4.6.9-1
Ubuntu1 product
- wiresharkAll versions (No fix recorded)
Wireshark1 product
- wireshark≥ 4.4.0, < 4.4.18 | ≥ 4.6.0, < 4.6.8
Wireshark foundation1 product
- wireshark≥ 4.6.0, < 4.6.8 | ≥ 4.4.0, < 4.4.18
4 vendors · 4 products
