Origin validation error in Mozilla Thunderbird
Priority LOW 21CWE-346Published · 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: 9 fixed, 1 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-346.
Summary
By encoding Unicode whitespace characters within the From email header, an attacker can spoof the sender email address that Thunderbird displays. This vulnerability affects Thunderbird < 68.8.0.
Why it matters now
EPSS 0.00612 49th percentileScored 2026-11-07
Fix Partial Thunderbird (Mozilla): 68.8.0Red Hat: 5 advisoriesRed Hat: 9 fixed, 1 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Mozilla | Thunderbird | before 68.8.0 | 68.8.0 | Patch available | CNA |
- Thunderbird VendorMozilla Affected before 68.8.0 Fixed in 68.8.0 Patch available CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* | before 68.8.0 | Vulnerable | Mozilla |
| cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:* | 16.04 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* | 18.04 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:* | 19.10 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:* | 20.04 | Vulnerable | Canonical |
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* Versions before 68.8.0 Vulnerable ·Mozilla
- cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:* Versions 16.04 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:* Versions 19.10 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:* Versions 20.04 Vulnerable ·Canonical
Remediation
- Fix · CNA Thunderbird (Mozilla) Fixed in 68.8.0
Red Hat 5 advisories
- RHSA-2020:2050 Released 2020-05-11 · Red Hat rating Criticalthunderbird security update
- Red Hat Enterprise Linux Client (v. 7) thunderbird-68.8.0-1.el7_8
- Red Hat Enterprise Linux Server Optional (v. 7) thunderbird-68.8.0-1.el7_8
- Red Hat Enterprise Linux Workstation (v. 7) thunderbird-68.8.0-1.el7_8
- RHSA-2020:2049 Released 2020-05-11 · Red Hat rating Criticalthunderbird security update
- Red Hat Enterprise Linux Desktop (v. 6) thunderbird-68.8.0-1.el6_10
- Red Hat Enterprise Linux Server Optional (v. 6) thunderbird-68.8.0-1.el6_10
- Red Hat Enterprise Linux Workstation (v. 6) thunderbird-68.8.0-1.el6_10
- RHSA-2020:2046 Released 2020-05-11 · Red Hat rating Criticalthunderbird security update
- Red Hat Enterprise Linux AppStream (v. 8) thunderbird-68.8.0-1.el8_2
Show 2 more Red Hat advisories
- RHSA-2020:2047 Released 2020-05-11 · Red Hat rating Criticalthunderbird security update
- Red Hat Enterprise Linux AppStream EUS (v. 8.1) thunderbird-68.8.0-1.el8_1
- RHSA-2020:2048 Released 2020-05-11 · Red Hat rating Criticalthunderbird security update
- Red Hat Enterprise Linux AppStream E4S (v. 8.0) thunderbird-68.8.0-1.el8_0
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
Mozilla Thunderbird — USN-4373-1
5 records Highest priority Priority MEDIUM 2 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2020-05540 Out-of-bounds write in Mozilla Firefox ESRPriority MEDIUM 51
- TI-2020-09913 Out-of-bounds write in Mozilla Firefox ESRPriority MEDIUM 47
- TI-2020-09905 Race condition in Mozilla Firefox ESRPriority LOW 38
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 5 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2020:2046 |
| Red Hat Enterprise Linux AppStream E4S (v. 8.0) | Fixed | RHSA-2020:2048 |
| Red Hat Enterprise Linux AppStream EUS (v. 8.1) | Fixed | RHSA-2020:2047 |
| Red Hat Enterprise Linux Client (v. 7) | Fixed | RHSA-2020:2050 |
| Red Hat Enterprise Linux Desktop (v. 6) | Fixed | RHSA-2020:2049 |
| Red Hat Enterprise Linux Server Optional (v. 6) | Fixed | RHSA-2020:2049 |
| Red Hat Enterprise Linux Server Optional (v. 7) | Fixed | RHSA-2020:2050 |
| Red Hat Enterprise Linux Workstation (v. 6) | Fixed | RHSA-2020:2049 |
| Red Hat Enterprise Linux Workstation (v. 7) | Fixed | RHSA-2020:2050 |
Timeline
- 2026-10-02 Threatist record created from CVE-2020-12397
- 2026-10-03 Alias added: GHSA-mg46-fgw7-xxfg
References
More Mozilla Thunderbird vulnerabilities
- 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
Sources
- CVE-2020-12397 · CVE Program
- CVE-2020-12397 · NVD
- FIRST EPSS
- GHSA-mg46-fgw7-xxfg · GitHub Advisory Database · CC BY 4.0
- CVE-2020-12397 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences