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CVE

CVE-2021-38492

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

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.

MEDIUM · CVSS 6.5 EPSS 0.00406
Schedule remediation
  • Public exploit or PoC is available
Sigma rules8 YARA rules0
▤

Affected Products & Versions

5
mozilla firefox< 92.0
mozilla firefox>= 91.0 and < 91.1
mozilla firefox esr< 78.14
mozilla thunderbird< 78.14
mozilla thunderbird>= 91.0 and < 91.1
⚠

Public Exploits & PoCs

1
pocbugzilla.mozilla.org · show_bug.cgi?id=1721107bugzilla.mozilla.org
◈

Sigma Hunt Rules

8
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
productcriticalHackTool - Windows Credential Editor (WCE) Execution
productcriticalWindows Credential Editor Registry
producthighOpenCanary - MSSQL Login Attempt Via Windows Authentication
producthighWindows LAPS Credential Dump From Entra ID
producthighTamper Windows Defender - PSClassic
producthighTamper Windows Defender Remove-MpPreference - ScriptBlockLogging
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · security@mozilla.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD03 Nov 2021 · 01:15 AM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
⚑

Vendor Advisories

17
suse-csafopenSUSE-SU-2024:14572-1
suse-csafopenSUSE-SU-2024:10600-1
suse-csafopenSUSE-SU-2024:10601-1
suse-csafSUSE-SU-2022:1577-1
suse-csafSUSE-SU-2022:1582-1
🔗

References & Sources

6
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://security.gentoo.org/glsa/202208-14Third Party 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
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