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TI-2020-05505 Aliases CVE-2020-6795GHSA-4whv-ch98-q6fp

NULL pointer dereference in Mozilla Thunderbird

Priority LOW 31CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 8 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

When processing a message that contains multiple S/MIME signatures, a bug in the MIME processing code caused a null pointer dereference, leading to an unexploitable crash. This vulnerability affects Thunderbird < 68.5.

Why it matters now

EPSS 0.01305 70th percentileScored 2026-11-07
Fix Partial Thunderbird (Mozilla): 68.5Red Hat: 4 advisoriesRed Hat: 8 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 68.568.5Patch availableCNA
  • Thunderbird VendorMozilla Affected before 68.5 Fixed in 68.5 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 68.5.0VulnerableMozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 68.5.0 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Thunderbird (Mozilla) Fixed in 68.5

Red Hat 4 advisories

  • RHSA-2020:0576 Released 2020-02-24 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux Client (v. 7) thunderbird-68.5.0-1.el7_7
    • Red Hat Enterprise Linux Server Optional (v. 7) thunderbird-68.5.0-1.el7_7
    • Red Hat Enterprise Linux Workstation (v. 7) thunderbird-68.5.0-1.el7_7
  • RHSA-2020:0574 Released 2020-02-24 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux Desktop (v. 6) thunderbird-68.5.0-1.el6_10
    • Red Hat Enterprise Linux Server Optional (v. 6) thunderbird-68.5.0-1.el6_10
    • Red Hat Enterprise Linux Workstation (v. 6) thunderbird-68.5.0-1.el6_10
  • RHSA-2020:0577 Released 2020-02-24 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-68.5.0-1.el8_1
Show 1 more Red Hat advisories
  • RHSA-2020:0565 Released 2020-02-20 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream E4S (v. 8.0) thunderbird-68.5.0-1.el8_0

Fixed in the same release

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

  • Release ·

    Mozilla Thunderbird 68.5

    5 records Highest priority Priority LOW 5 LOW

    Other records, highest priority first

    • TI-2020-05503 Use of uninitialized resource in Mozilla ThunderbirdPriority LOW 32
    • TI-2020-05504 Cleartext storage of sensitive information in Mozilla ThunderbirdPriority LOW 31
    • TI-2020-05507 Improper input validation in Mozilla ThunderbirdPriority LOW 23
    Show all 5 records →

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2020:0577
Red Hat Enterprise Linux AppStream E4S (v. 8.0)Fixed RHSA-2020:0565
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2020:0576
Red Hat Enterprise Linux Desktop (v. 6)Fixed RHSA-2020:0574
Red Hat Enterprise Linux Server Optional (v. 6)Fixed RHSA-2020:0574
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2020:0576
Red Hat Enterprise Linux Workstation (v. 6)Fixed RHSA-2020:0574
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2020:0576

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-6795
  2. 2026-10-03 Alias added: GHSA-4whv-ch98-q6fp

References

Advisory 4

Other 1

  • 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