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TI-2020-12359 Aliases CVE-2020-15685GHSA-c839-4fpv-9xp7

Command injection in Mozilla Thunderbird

Priority HIGH 73CWE-77Published · Updated

Key facts

Attack vector
Network
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 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-77.

Summary

During the plaintext phase of the STARTTLS connection setup, protocol commands could have been injected and evaluated within the encrypted session. This vulnerability affects Thunderbird < 78.7.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00881 59th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Thunderbird (Mozilla): 78.7Red Hat: 4 advisoriesRed Hat: 6 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MozillaThunderbirdbefore 78.778.7Patch availableCNA
  • Thunderbird VendorMozilla Affected before 78.7 Fixed in 78.7 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*before 78.7.0VulnerableMozilla
  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 78.7.0 Vulnerable ·Mozilla

Remediation

  • Fix · CNA Thunderbird (Mozilla) Fixed in 78.7

Red Hat 4 advisories

  • RHSA-2021:0397 Released 2021-02-03 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.1) thunderbird-78.7.0-1.el8_1
  • RHSA-2021:0298 Released 2021-01-28 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream (v. 8) thunderbird-78.7.0-1.el8_3
  • RHSA-2021:0297 Released 2021-01-28 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux Client (v. 7) thunderbird-78.7.0-1.el7_9
    • Red Hat Enterprise Linux Server Optional (v. 7) thunderbird-78.7.0-1.el7_9
    • Red Hat Enterprise Linux Workstation (v. 7) thunderbird-78.7.0-1.el7_9
Show 1 more Red Hat advisories
  • RHSA-2021:0299 Released 2021-01-28 · Red Hat rating Important
    thunderbird security update
    • Red Hat Enterprise Linux AppStream EUS (v. 8.2) thunderbird-78.7.0-1.el8_2

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-2021:0298
Red Hat Enterprise Linux AppStream EUS (v. 8.1)Fixed RHSA-2021:0397
Red Hat Enterprise Linux AppStream EUS (v. 8.2)Fixed RHSA-2021:0299
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2021:0297
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2021:0297
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2021:0297

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-15685
  2. 2026-10-03 Alias added: GHSA-c839-4fpv-9xp7

References

Exploit 1

Advisory 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