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TI-2021-10566 Aliases CVE-2021-29949GHSA-mhf4-98x7-2cw4

Uncontrolled search path in Mozilla Thunderbird

Priority LOW 34CWE-427Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
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-427.

Summary

When loading the shared library that provides the OTR protocol implementation, Thunderbird will initially attempt to open it using a filename that isn't distributed by Thunderbird. If a computer has already been infected with a malicious library of the alternative filename, and the malicious library has been copied to a directory that is contained in the search path for executable libraries, then Thunderbird will load the incorrect library. This vulnerability affects Thunderbird < 78.9.1.

Why it matters now

EPSS 0.00316 24th 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-2021-06310 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
    • TI-2021-06311 Improper signature verification in Mozilla ThunderbirdPriority LOW 21
    Show all 4 records →

Vendor assessments

Red Hat

Red Hat rating: Low. 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-2021-29949
  2. 2026-10-03 Alias added: GHSA-mhf4-98x7-2cw4

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