Back
CVE-2020-15917
common/session.c in Claws Mail before 3.17.6 has a protocol violation because suffix data after STARTTLS is mishandled.
- 9.8CriticalCVSS base score
- 2.6%Exploitation in 30 daysEPSS · top 14% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
common/session.c in Claws Mail before 3.17.6 has a protocol violation because suffix data after STARTTLS is mishandled.
Timeline
ID reserved
By mitre
Published
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 2.6% · top 14% of all CVEs (10 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
n/a
- affected n/a
References
10
- https://git.claws-mail.org/?p=claws.git%3Ba=commit%3Bh=fcc25329049b6f9bd8d890f1197ed61eb12e14d5 (opens in a new tab)x_refsource_MISCx_transferred
- https://git.claws-mail.org/?p=claws.git%3Ba=blob%3Bf=RELEASE_NOTES (opens in a new tab)x_refsource_MISCx_transferred
- GLSA-202007-56 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
- openSUSE-SU-2020:1116 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- FEDORA-2020-2def860ce7 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- FEDORA-2020-fe6c1a9c16 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- openSUSE-SU-2020:1139 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- openSUSE-SU-2020:1269 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- openSUSE-SU-2020:1192 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- openSUSE-SU-2020:1822 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_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)
- EUVD EUVD-2020-7889 (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://cveledger.app/cve/CVE-2020-15917)Record last updated .