CVE-2025-9181: mozilla firefox Use of Uninitialized Variable
CVSS: 6.5v3.1MediumModified
AliasesUBUNTU-CVE-2025-9181DEBIAN-CVE-2025-9181CGA-qvcw-ph29-5fc2CGA-w74m-xxg7-mf6hCGA-8g8v-pghv-q57mCGA-9jgw-9cvj-f9j7
Published 19-08-2025Last modified 13-04-2026
Vulnerability summary
CVE-2025-9181 is a medium (CVSS 6.5) Use of Uninitialized Variable vulnerability in mozilla firefox. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 31.5% of scored vulnerabilities.
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)EPSS score
0.39%
0%100%
Low · +0.03 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 37 · Related 13DLA-4277-1DLA-4279-1DSA-5980-1DSA-5984-1MGASA-2025-0227MGASA-2025-0228OPENSUSE-SU-2025-20135-1OPENSUSE-SU-2025:15467-1OPENSUSE-SU-2025:15472-1OPENSUSE-SU-2025:15494-1OPENSUSE-SU-2025:15516-1OPENSUSE-SU-2025:20135-1RHSA-2025:14416RHSA-2025:14417RHSA-2025:14442RHSA-2025:14640RHSA-2025:14743RHSA-2025:14844RHSA-2025:15418RHSA-2025:15419RHSA-2025:15420RHSA-2025:15421RHSA-2025:15422RHSA-2025:15423RHSA-2025:15424RHSA-2025:15430RHSA-2025:15434RHSA-2025:15435RHSA-2025:15436RHSA-2025:15437RHSA-2025:15438RHSA-2025:15496RHSA-2025:15535SUSE-SU-2025:03007-1SUSE-SU-2025:03008-1SUSE-SU-2025:03009-1SUSE-SU-2025:21170-1CGA-FJW7-G96H-M6WQCGA-M5MC-C498-FX4GUSN-7991-1
Timeline
- 19-08-2025PublishedVulnerability first disclosed.
- 13-04-2026Last modifiedVulnerability information updated.
Description
Uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 142, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.
CVSS metrics
6 scores · 6 sources · 1 versionMedium 6.5Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:NSourcesAll 6 agree
- OSV · UbuntuEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- OSV · DebianEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- OSV · WolfiEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- OSV · ChainguardEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- NVDNIST6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS trend
Probability
0.39%
Chance of exploitation in the next 30 days
Percentile
32%
Versus all other CVEs
30-day change
+0.03 pp
From 0.36% on 19-09-2026
19-09-202619-10-2026
EPSS score0.39%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected 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< 128.14-r0
- firefox-esr< 140.2-r0
Debian2 products
- firefox-esr< 128.14.0esr-1~deb12u1 | < 128.14.0esr-1~deb13u1 | < 128.14.0esr-1
- thunderbird< 1:128.14.0esr-1~deb12u1 | < 1:128.14.0esr-1~deb13u1 | < 1:128.14.0esr-1
Mozilla2 products
- firefox< 128.14.0 | < 142.0 | ≥ 140.0, < 140.2.0
- thunderbird< 128.14.0 | < 142.0 | ≥ 140.0, < 140.2.0
Wolfi1 product
- firefox< 128.14-r0
5 vendors · 15 products
