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TI-2021-06298 Aliases CVE-2021-23977GHSA-cc5x-973x-6p4m

Time-of-check time-of-use race condition in Mozilla Firefox

Priority LOW 26CWE-367Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

Firefox for Android suffered from a time-of-check-time-of-use vulnerability that allowed a malicious application to read sensitive data from application directories. Note: This issue is only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 86.

Why it matters now

EPSS 0.00881 59th percentileScored 2026-11-07
Fix Fixed Firefox (Mozilla): 86

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaFirefoxbefore 8686Patch availableCNA
  • Firefox VendorMozilla Affected before 86 Fixed in 86 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:android:*:*before 86.0VulnerableMozilla
  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:android:*:* Versions before 86.0 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Firefox (Mozilla) Fixed in 86

Fixed in the same release

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

  • Advisory ·

    Mozilla Firefox — GLSA-202104-10

    12 records Highest priority Priority MEDIUM 2 MEDIUM, 10 LOW

    Other records, highest priority first

    • TI-2021-06299 Out-of-bounds write in Mozilla FirefoxPriority MEDIUM 41
    • TI-2021-06293 One phishing tactic on the web is to provide a link with HTTP Auth.Priority MEDIUM 40
    • TI-2021-06297 Clickjacking in Mozilla FirefoxPriority LOW 37
    Show all 12 records → Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-23977
  2. 2026-10-03 Alias added: GHSA-cc5x-973x-6p4m

References

Advisory 3

  • 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