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TI-2021-16097 Aliases CVE-2021-38497GHSA-qmc5-2jh2-rpcw

Origin validation error in Mozilla Firefox

Priority LOW 30CWE-346Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
Partial Red Hat: 9 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-346.

Summary

Through use of reportValidity() and window.open(), a plain-text validation message could have been overlaid on another origin, leading to possible user confusion and spoofing attacks. This vulnerability affects Firefox < 93, Thunderbird < 91.2, and Firefox ESR < 91.2.

Why it matters now

EPSS 0.00591 48th percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 93Thunderbird (Mozilla): 91.2+1 more productRed Hat: 8 advisoriesRed Hat: 9 fixed, 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaFirefoxbefore 9393Patch availableCNA
MozillaThunderbirdbefore 91.291.2Patch availableCNA
MozillaFirefox ESRbefore 91.291.2Patch availableCNA
  • Firefox VendorMozilla Affected before 93 Fixed in 93 Patch available CNA
  • Thunderbird VendorMozilla Affected before 91.2 Fixed in 91.2 Patch available CNA
  • Firefox ESR VendorMozilla Affected before 91.2 Fixed in 91.2 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*before 93.0VulnerableMozilla
cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*before 91.2VulnerableMozilla
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 91.2VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* Versions before 93.0 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:* Versions before 91.2 Vulnerable ·Mozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 91.2 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 93
  • Fix · CNA Thunderbird (Mozilla) Fixed in 91.2
  • Fix · CNA Firefox ESR (Mozilla) Fixed in 91.2

Red Hat 8 advisories

  • RHSA-2021:3841 Released 2021-10-13 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux Client (v. 7) thunderbird-91.2.0-1.el7_9
    • Red Hat Enterprise Linux Server Optional (v. 7) thunderbird-91.2.0-1.el7_9
    • Red Hat Enterprise Linux Workstation (v. 7) thunderbird-91.2.0-1.el7_9
  • RHSA-2021:3838 Released 2021-10-13 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-91.2.0-1.el8_4
  • RHSA-2021:3839 Released 2021-10-13 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.2) thunderbird-91.2.0-1.el8_2
Show 5 more Red Hat advisories
  • RHSA-2021:3840 Released 2021-10-13 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.1) thunderbird-91.2.0-1.el8_1
  • RHSA-2021:3791 Released 2021-10-12 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux Client (v. 7) firefox-91.2.0-4.el7_9
    • Red Hat Enterprise Linux Client Optional (v. 7) firefox-91.2.0-4.el7_9
    • Red Hat Enterprise Linux Server (v. 7) firefox-91.2.0-4.el7_9
    • Red Hat Enterprise Linux Server Optional (v. 7) firefox-91.2.0-4.el7_9
    • Red Hat Enterprise Linux Workstation (v. 7) firefox-91.2.0-4.el7_9
    • Red Hat Enterprise Linux Workstation Optional (v. 7) firefox-91.2.0-4.el7_9
  • RHSA-2021:3755 Released 2021-10-11 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream (v. 8) firefox-91.2.0-4.el8_4
  • RHSA-2021:3757 Released 2021-10-11 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.1) firefox-91.2.0-4.el8_1
  • RHSA-2021:3756 Released 2021-10-11 · Red Hat rating Important
    firefox security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.2) firefox-91.2.0-4.el8_2

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Mozilla Firefox 93

    6 records Highest priority Priority MEDIUM 4 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2021-16100 Mozilla developers reported memory safety bugs present in Firefox 92 and Firefox ESR 91.1.Priority MEDIUM 41
    • TI-2021-16096 Use after free in Mozilla ThunderbirdPriority MEDIUM 41
    • TI-2021-16101 Mozilla developers reported memory safety bugs present in Firefox 92 and Firefox ESR 91.1.Priority MEDIUM 40
    Show all 6 records →
  • Release ·

    Mozilla Thunderbird 91.2

    4 records Highest priority Priority MEDIUM 1 MEDIUM, 3 LOW

    Other records, highest priority first

    • TI-2021-16101 Mozilla developers reported memory safety bugs present in Firefox 92 and Firefox ESR 91.1.Priority MEDIUM 40
    • TI-2021-16098 Use after free in Mozilla FirefoxPriority LOW 36
    • TI-2021-16102 Thunderbird ignored the configuration to require STARTTLS security for an SMTP connection.Priority LOW 29
    Show all 4 records →
Show 1 more group
  • Release ·

    Mozilla Firefox ESR 91.2

    3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2021-16101 Mozilla developers reported memory safety bugs present in Firefox 92 and Firefox ESR 91.1.Priority MEDIUM 40
    • TI-2021-16098 Use after free in Mozilla FirefoxPriority LOW 36
    Show all 3 records →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2021:3755, RHSA-2021:3838
Red Hat Enterprise Linux AppStream EUS (v. 8.1)Fixed RHSA-2021:3757, RHSA-2021:3840
Red Hat Enterprise Linux AppStream EUS (v. 8.2)Fixed RHSA-2021:3756, RHSA-2021:3839
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2021:3791, RHSA-2021:3841
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2021:3791
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2021:3791
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2021:3791, RHSA-2021:3841
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2021:3791, RHSA-2021:3841
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2021:3791

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-38497
  2. 2026-10-03 Alias added: GHSA-qmc5-2jh2-rpcw

References

Advisory 4

  • TI-2024-08981 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.8
  • TI-2022-09832 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.6
  • TI-2019-08769 Improper input validation in Mozilla Firefox ESR KEVCVSS 3.1CRITICAL 10.0
  • TI-2010-03577 Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before… KEVCVSS 3.1CRITICAL 9.8
  • TI-2023-04799 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
  • TI-2023-04477 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
See all 3444 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences