CVE-2025-1013 | Potential opening of private browsing tabs in normal browsing windows

A race condition could have led to private browsing tabs being opened in normal browsing windows. This could have resulted in a potential privacy leak. This vulnerability was fixed in Firefox 135, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.

Published: 2025-02-04 Last update: 2026-04-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-1013 is rated Moderate Risk (44.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.29%). 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-2025-1013

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 2026-03-02 0.39% 0.29% -0.10%
2 2025-12-01 0.31% 0.39% +0.09%
3 2025-11-04 — 0.31% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-1013

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N 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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 2.5 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2025-1013

OS Trackers for CVE-2025-1013

vendor priority summary link
alpine — CVE-2025-1013: 3 source package rows (firefox, firefox-esr, thunderbird); 339 state rows across 2 repos (3.22-community, edge-community); fixed 0, open 339. https://security.alpinelinux.org/vuln/CVE-2025-1013
debian not yet assigned CVE-2025-1013 not yet assigned priority: Debian including 3 source packages (firefox, firefox-esr, thunderbird), 11 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 11. https://security-tracker.debian.org/tracker/CVE-2025-1013
redhat low — https://access.redhat.com/security/cve/CVE-2025-1013
suse high CVE-2025-1013 severity important: SUSE including 37 source package names (MozillaFirefox-128.7.0-112.246.1, MozillaFirefox-128.7.0-150200.152.170.1, …), 139 product×package rows across 48 product lines (Container suse/kiosk/firefox-esr, Image SLES12-SP5-SAP-Azure-LI-BYOS-Production, … (48 product lines)): Fixed 139. https://www.suse.com/security/cve/CVE-2025-1013/
ubuntu medium CVE-2025-1013 medium priority: Ubuntu including 9 source packages (firefox, mozjs102, …), 65 status rows across 8 suites (bionic, focal, jammy, noble, oracular, plucky, questing, upstream): DNE 34, ignored 10, needs-triage 9, not-affected 9, released 3. https://ubuntu.com/security/CVE-2025-1013

Affected software / configurations for CVE-2025-1013

Vendor Product Version Raw CPE
mozilla firefox < 128.7.0 cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
mozilla firefox < 135.0 cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
mozilla thunderbird < 128.7.0 cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
mozilla thunderbird >= 129.0, < 135.0 cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

References for CVE-2025-1013

cvelogic Threat Intelligence