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TI-2021-06311 Aliases CVE-2021-23992GHSA-x89c-f42w-ch2g

Improper signature verification in Mozilla Thunderbird

Priority LOW 21CWE-347Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
Partial Red Hat: 6 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-347.

Summary

Thunderbird did not check if the user ID associated with an OpenPGP key has a valid self signature. An attacker may create a crafted version of an OpenPGP key, by either replacing the original user ID, or by adding another user ID. If Thunderbird imports and accepts the crafted key, the Thunderbird user may falsely conclude that the false user ID belongs to the correspondent. This vulnerability affects Thunderbird < 78.9.1.

Why it matters now

EPSS 0.00478 41st percentileScored 2026-11-07
Fix Partial Thunderbird (Mozilla): 78.9.1Red Hat: 4 advisoriesRed Hat: 6 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
MozillaThunderbirdbefore 78.9.178.9.1Patch availableCNA
  • Thunderbird VendorMozilla Affected before 78.9.1 Fixed in 78.9.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 78.9.1VulnerableMozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 78.9.1 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Thunderbird (Mozilla) Fixed in 78.9.1

Red Hat 4 advisories

  • RHSA-2021:1201 Released 2021-04-14 · Red Hat rating Moderate
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.2) thunderbird-78.9.1-1.el8_2
  • RHSA-2021:1192 Released 2021-04-14 · Red Hat rating Moderate
    thunderbird security update
    • Red Hat Enterprise Linux Client (v. 7) thunderbird-78.9.1-1.el7_9
    • Red Hat Enterprise Linux Server Optional (v. 7) thunderbird-78.9.1-1.el7_9
    • Red Hat Enterprise Linux Workstation (v. 7) thunderbird-78.9.1-1.el7_9
  • RHSA-2021:1193 Released 2021-04-14 · Red Hat rating Moderate
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-78.9.1-1.el8_3
Show 1 more Red Hat advisories
  • RHSA-2021:1190 Released 2021-04-14 · Red Hat rating Moderate
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.1) thunderbird-78.9.1-1.el8_1

Fixed in the same release

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

  • Release ·

    Mozilla Thunderbird 78.9.1

    4 records Highest priority Priority LOW 4 LOW

    Other records, highest priority first

    • TI-2021-10566 Uncontrolled search path in Mozilla ThunderbirdPriority LOW 34
    • TI-2021-06310 If a Thunderbird user has previously imported Alice's OpenPGP key, and Alice has extended…Priority LOW 32
    • TI-2021-06312 Improper signature verification in Mozilla ThunderbirdPriority LOW 29
    Show all 4 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-2021:1193
Red Hat Enterprise Linux AppStream EUS (v. 8.1)Fixed RHSA-2021:1190
Red Hat Enterprise Linux AppStream EUS (v. 8.2)Fixed RHSA-2021:1201
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2021:1192
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2021:1192
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2021:1192

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-23992
  2. 2026-10-03 Alias added: GHSA-x89c-f42w-ch2g

References

Advisory 2

  • 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 2067 →

Sources

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