CVE-2025-11712
published 2025-10-14CVE-2025-11712: A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a…
PriorityP425medium6.1CVSS 3.1
AVNACLPRNUIRSCCLILAN
EPSS
0.26%
17.0th percentile
A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. This could have contributed to an XSS on a site that unsafely serves files without a content-type header. This vulnerability was fixed in Firefox 144, Firefox ESR 140.4, Thunderbird 144, and Thunderbird 140.4.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 144.0-1 (sid) | firefox 144.0-1 (sid) |
| debian | firefox-esr | < firefox 144.0-1 (sid) | firefox 144.0-1 (sid) |
| debian | thunderbird | < firefox 144.0-1 (sid) | firefox 144.0-1 (sid) |
| mozilla | firefox | < 140.4.0 | 140.4.0 |
| mozilla | firefox | < 144.0 | 144.0 |
| mozilla | firefox | — | — |
| mozilla | thunderbird | < 140.4.0 | 140.4.0 |
| mozilla | thunderbird | >= 0 < 1:140.4.0esr-1~deb11u1 | 1:140.4.0esr-1~deb11u1 |
| mozilla | thunderbird | >= 0 < 1:140.4.0esr-1~deb12u1 | 1:140.4.0esr-1~deb12u1 |
| mozilla | thunderbird | >= 0 < 1:140.4.0esr-1~deb13u1 | 1:140.4.0esr-1~deb13u1 |
| mozilla | thunderbird | >= 0 < 1:140.4.0esr-1 | 1:140.4.0esr-1 |
| mozilla | thunderbird | >= 141.0 < 144.0 | 144.0 |
CVSS provenance
nvdv3.16.1MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
osv6.1MEDIUM
vendor_debian6.1MEDIUM
vendor_redhat6.1MEDIUM
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Ubuntu
Thunderbird vulnerabilities
vendor_ubuntu·2026-02-02
CVE-2025-8031 Thunderbird vulnerabilities
Title: Thunderbird vulnerabilities
Summary: Several security issues were fixed in Thunderbird.
Multiple security issues were discovered in Thunderbird. If a user were
tricked into opening a specially crafted website in a browsing context,
an attacker could potentially exploit these to cause a denial of service,
obtain sensitive information, bypass security restrictions, cross-site
tracing, or execute arbitrary code.
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
thunderbird: firefox: An OBJECT tag type attribute overrode browser behavior on web resources without a content-type
vendor_redhat·2025-10-14·CVSS 6.1
CVE-2025-11712 [MEDIUM] CWE-436 thunderbird: firefox: An OBJECT tag type attribute overrode browser behavior on web resources without a content-type
thunderbird: firefox: An OBJECT tag type attribute overrode browser behavior on web resources without a content-type
A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. This could have contributed to an XSS on a site that unsafely serves files without a content-type header. This vulnerability affects Firefox < 144, Firefox ESR < 140.4, Thunderbird < 144, and Thunderbird < 140.4.
A flaw was found in Thunderbird and Firefox. The Mozilla Foundation's Security Advisory describes the following issue:
A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. T
Debian
CVE-2025-11712: firefox - A malicious page could have used the type attribute of an OBJECT tag to override...
vendor_debian·2025·CVSS 6.1
CVE-2025-11712 [MEDIUM] CVE-2025-11712: firefox - A malicious page could have used the type attribute of an OBJECT tag to override...
A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. This could have contributed to an XSS on a site that unsafely serves files without a content-type header. This vulnerability affects Firefox < 144, Firefox ESR < 140.4, Thunderbird < 144, and Thunderbird < 140.4.
Scope: local
sid: resolved (fixed in 144.0-1)
Mozilla
Mozilla Foundation Security Advisory 2025-81: CVE-2025-11712
vendor_mozilla·CVSS 6.1
CVE-2025-11712 [MEDIUM] Mozilla Foundation Security Advisory 2025-81: CVE-2025-11712
Mozilla Foundation Security Advisory 2025-81
CVE: CVE-2025-11712
Product: Firefox
Impact: high
Fixed in: Firefox 144
Mozilla
Mozilla Foundation Security Advisory 2025-83: CVE-2025-11712
vendor_mozilla·CVSS 6.1
CVE-2025-11712 [MEDIUM] Mozilla Foundation Security Advisory 2025-83: CVE-2025-11712
Mozilla Foundation Security Advisory 2025-83
CVE: CVE-2025-11712
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.4
Mozilla
Mozilla Foundation Security Advisory 2025-85: CVE-2025-11712
vendor_mozilla·CVSS 6.1
CVE-2025-11712 [MEDIUM] Mozilla Foundation Security Advisory 2025-85: CVE-2025-11712
Mozilla Foundation Security Advisory 2025-85
CVE: CVE-2025-11712
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.4
Mozilla
Mozilla Foundation Security Advisory 2025-84: CVE-2025-11712
vendor_mozilla·CVSS 6.1
CVE-2025-11712 [MEDIUM] Mozilla Foundation Security Advisory 2025-84: CVE-2025-11712
Mozilla Foundation Security Advisory 2025-84
CVE: CVE-2025-11712
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 144
GHSA
GHSA-rf6g-cf9f-g4v7: A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served
ghsa_unreviewed·2025-10-14
CVE-2025-11712 [MEDIUM] CWE-116 GHSA-rf6g-cf9f-g4v7: A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served
A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. This could have contributed to an XSS on a site that unsafely serves files without a content-type header. This vulnerability affects Firefox < 144, Firefox ESR < 140.4, Thunderbird < 144, and Thunderbird < 140.4.
OSV
CVE-2025-11712: A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served
osv·2025-10-14·CVSS 6.1
CVE-2025-11712 [MEDIUM] CVE-2025-11712: A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served
A malicious page could have used the type attribute of an OBJECT tag to override the default browser behavior when encountering a web resource served without a content-type. This could have contributed to an XSS on a site that unsafely serves files without a content-type header. This vulnerability affects Firefox < 144, Firefox ESR < 140.4, Thunderbird < 144, and Thunderbird < 140.4.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=1979536https://www.mozilla.org/security/advisories/mfsa2025-81/https://www.mozilla.org/security/advisories/mfsa2025-83/https://www.mozilla.org/security/advisories/mfsa2025-84/https://www.mozilla.org/security/advisories/mfsa2025-85/https://lists.debian.org/debian-lts-announce/2025/10/msg00015.htmlhttps://lists.debian.org/debian-lts-announce/2025/10/msg00031.html
2025-10-14
Published