CVE-2021-38492

6.5 MEDIUM

When delegating navigations to the operating system, Firefox would accept the `mk` scheme which might allow attackers to launch pages and...

Published: 2021-11-03 · Last updated: 2026-06-17

Severity and scoring

CVSS: 6.5 MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Affected products

Vendor	Product
mozilla	firefox, firefox_esr, thunderbird

Description

When delegating navigations to the operating system, Firefox would accept the `mk` scheme which might allow attackers to launch pages and execute scripts in Internet Explorer in unprivileged mode. *This bug only affects Firefox for Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 92, Thunderbird < 91.1, Thunderbird < 78.14, Firefox ESR < 78.14, and Firefox ESR < 91.1.

Source: NVD

References

[NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-38492
[Vendor advisory]https://bugzilla.mozilla.org/show_bug.cgi?id=1721107
[Other]https://security.gentoo.org/glsa/202208-14
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-38/
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-39/
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-40/
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-41/
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-42/
[Vendor advisory]https://bugzilla.mozilla.org/show_bug.cgi?id=1721107
[Other]https://security.gentoo.org/glsa/202208-14
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-38/
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-39/
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-40/
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-41/
[Vendor advisory]https://www.mozilla.org/security/advisories/mfsa2021-42/

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