8.1

CVE-2026-4718: Undefined behavior in the WebRTC: Signaling component

Modified
AliasesUBUNTU-CVE-2026-4718DEBIAN-CVE-2026-4718CGA-grmq-pf6j-wc28
Published 24-03-2026Last modified 13-04-2026

Vulnerability summary

CVE-2026-4718 is a high (CVSS 8.1) vulnerability in mozilla firefox. EPSS estimates a 0.48% chance of exploitation in the next 30 days, higher than 41.5% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 8.1, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.48%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 39 · Related 9
DLA-4510-1DLA-4511-1DSA-6178-1DSA-6179-1MGASA-2026-0080MGASA-2026-0081

Timeline

  1. 24-03-2026
    PublishedVulnerability first disclosed.
  2. 13-04-2026
    Last modifiedVulnerability information updated.

Description

Undefined behavior in the WebRTC: Signaling component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.48%

Chance of exploitation in the next 30 days

Percentile

42%

Versus all other CVEs

30-day change

Increase +0.02 pp

From 0.46% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu8 products
  • mozjs102All versions (No fix recorded)
  • mozjs115All versions (No fix recorded)
  • mozjs38All versions (No fix recorded)
  • mozjs52All versions (No fix recorded)
  • mozjs68All versions (No fix recorded)
Chainguard2 products
  • firefox< 149.0-r0
  • firefox-esr< 140.9-r0
Debian2 products
  • firefox-esr< 140.9.0esr-1~deb12u1 | < 140.9.0esr-1~deb13u1 | < 140.9.0esr-1
  • thunderbird< 1:140.9.0esr-1~deb12u1 | < 1:140.9.0esr-1~deb13u1 | < 1:140.9.0esr-1
Mozilla2 products
Wolfi1 product
  • firefox< 149.0-r0

5 vendors · 15 products

References

11 links
Show all 11 references