CVE-2025-8036 | DNS rebinding circumvents CORS

Thunderbird cached CORS preflight responses across IP address changes. This allowed circumventing CORS with DNS rebinding. This vulnerability was fixed in Firefox 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.

Published: 2025-07-22 Last update: 2026-04-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-8036 is rated Moderate Risk (50.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.27%). 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-2025-8036

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 2026-05-18 0.05% 0.27% +0.22%
2 2026-03-27 0.03% 0.05% +0.02%
3 2025-12-18 — 0.03% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-8036

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.1 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 5.2 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2025-8036

OS Trackers for CVE-2025-8036

vendor priority summary link
alpine — CVE-2025-8036: 3 source package rows (firefox, firefox-esr, thunderbird); 381 state rows across 2 repos (3.22-community, edge-community); fixed 0, open 381. https://security.alpinelinux.org/vuln/CVE-2025-8036
debian not yet assigned CVE-2025-8036 not yet assigned priority: Debian including 1 source packages (firefox), 1 status rows across 1 suites (sid): resolved 1. https://security-tracker.debian.org/tracker/CVE-2025-8036
redhat medium — https://access.redhat.com/security/cve/CVE-2025-8036
suse high CVE-2025-8036 severity important: SUSE including 67 source package names (MozillaFirefox-140.1.0-112.273.1, MozillaFirefox-140.1.0-150200.152.193.1, …), 335 product×package rows across 42 product lines (Image SLES12-SP5-SAP-Azure-LI-BYOS-Production, Image SLES12-SP5-SAP-Azure-VLI-BYOS-Production, … (42 product lines)): Fixed 335. https://www.suse.com/security/cve/CVE-2025-8036/
ubuntu medium CVE-2025-8036 medium priority: Ubuntu including 9 source packages (firefox, mozjs102, …), 49 status rows across 7 suites (bionic, focal, jammy, noble, plucky, questing, upstream): DNE 22, ignored 9, needs-triage 9, not-affected 7, released 2. https://ubuntu.com/security/CVE-2025-8036

Affected software / configurations for CVE-2025-8036

Vendor Product Version Raw CPE
mozilla firefox < 140.1.0 cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
mozilla firefox < 141.0 cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
mozilla thunderbird < 140.1.0 cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
mozilla thunderbird < 141.0 cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*

References for CVE-2025-8036

cvelogic Threat Intelligence