CVE-2025-5262

A double-free could have occurred in `vpx_codec_enc_init_multi` after a failed allocation when initializing the encoder for WebRTC. This could have caused memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 139 and Thunderbird < 128.11.

Published: 2025-05-27 Last update: 2025-09-19 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-5262 is rated Moderate Risk (51/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.38%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-5262

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-23 0.06% 0.38% +0.32%
2 2025-11-04 0.05% 0.06% +0.01%
3 2025-10-24 — 0.05% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-5262

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2025-5262

OS Trackers for CVE-2025-5262

vendor priority summary link
alpine — CVE-2025-5262: 1 source package rows (thunderbird); 71 state rows across 2 repos (3.22-community, edge-community); fixed 0, open 71. https://security.alpinelinux.org/vuln/CVE-2025-5262
redhat critical — https://access.redhat.com/security/cve/CVE-2025-5262
ubuntu medium CVE-2025-5262 medium priority: Ubuntu including 9 source packages (firefox, mozjs102, …), 56 status rows across 7 suites (bionic, focal, jammy, noble, oracular, plucky, upstream): DNE 28, ignored 10, needs-triage 9, not-affected 9. https://ubuntu.com/security/CVE-2025-5262

Affected software / configurations for CVE-2025-5262

Vendor Product Version Raw CPE
mozilla thunderbird < 128.11.0 cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
mozilla thunderbird < 139.0 cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*

References for CVE-2025-5262

cvelogic Threat Intelligence