5.3

CVE-2026-0883: mozilla firefox

CVSS: 5.3v3.1MediumModified
AliasesUBUNTU-CVE-2026-0883DEBIAN-CVE-2026-0883CGA-2qf3-6vx7-mwjm
Published 13-01-2026Last modified 13-04-2026

Vulnerability summary

CVE-2026-0883 is a medium (CVSS 5.3) vulnerability in mozilla firefox. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 27.7% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.36%
0%100%
Low · -0.11 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 38 · Related 11

Timeline

  1. 13-01-2026
    PublishedVulnerability first disclosed.
  2. 13-04-2026
    Last modifiedVulnerability information updated.

Description

Information disclosure in the Networking component. This vulnerability was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.

CVSS metrics

6 scores · 6 sources · 1 version

EPSS trend

Probability

0.36%

Chance of exploitation in the next 30 days

Percentile

28%

Versus all other CVEs

30-day change

-0.11 pp

From 0.47% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.36%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

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< 140.7-r0
  • firefox-esr< 140.7-r0
Debian2 products
  • firefox-esr< 140.7.0esr-1~deb12u1 | < 140.7.0esr-1~deb13u1 | < 140.7.0esr-1
  • thunderbird< 1:140.7.0esr-1~deb12u1 | < 1:140.7.0esr-1~deb13u1 | < 1:140.7.0esr-1
Mozilla2 products
Wolfi1 product
  • firefox< 140.7-r0

5 vendors · 15 products

References

11 links
Show all 11 references