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CVE-2020-12397
By encoding Unicode whitespace characters within the From email header, an attacker can spoof the sender email address that Thunderbird…
Medium4.3EPSS 0.61%
- Published
- Updated
- Reserved
- Assigned by
- mozilla
Description
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.61% · top 50% of all CVEs (6 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.
Weakness
- Sender Email Address Spoofing using encoded Unicode characters
- CWE-346 (opens in a new tab)All about CWE-346 and its CVEs
Affected products
- affected unspecified – < 68.8.0
References (4)
- https://www.mozilla.org/security/advisories/mfsa2020-18/ (opens in a new tab)x_refsource_MISCx_transferred
- https://bugzilla.mozilla.org/show_bug.cgi?id=1617370 (opens in a new tab)x_refsource_MISCx_transferred
- USN-4373-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- https://security.gentoo.org/glsa/202005-03 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-12397)Record last updated .