In KDE KMail 19.12.3 (aka 5.13.3), the SMTP STARTTLS option is not honored (and cleartext…
Priority LOW 25CWE-319Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- High
- Impact type
- Information disclosure, Code execution
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Will not fix Red Hat: no fix planned
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-319 and CWE-77.
Summary
In KDE KMail 19.12.3 (aka 5.13.3), the SMTP STARTTLS option is not honored (and cleartext messages are sent) unless "Server requires authentication" is checked.
Why it matters now
EPSS 0.00527 44th percentileScored 2026-11-07
Fix Will not fix Red Hat: no fix planned
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 |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
Timeline
- 2026-10-02 Threatist record created from CVE-2021-38373
- 2026-10-03 Alias added: GHSA-rc8g-gfxp-864v
References
More KDE Kmail vulnerabilities
- TI-2016-06694 KMail since version 5.3.0 used a QWebEngine based viewer that had JavaScript enabled. CVSS 3.0HIGH 8.1
- TI-2016-06693 Through a malicious URL that contained a quote character it was possible to inject HTML… CVSS 3.0HIGH 7.3
- TI-2017-07005 KDE kmail before 5.5.2 and messagelib before 5.5.2, as distributed in KDE Applications… CVSS 3.0HIGH 7.5
- TI-2017-12946 The S/MIME specification allows a Cipher Block Chaining (CBC) malleability-gadget attack… CVSS 3.0MEDIUM 5.9
- TI-2020-09548 An issue was discovered in KDE KMail before 19.12.3. CVSS 3.1MEDIUM 6.5
- TI-2016-06695 KMail since version 5.3.0 used a QWebEngine based viewer that had JavaScript enabled. CVSS 3.0MEDIUM 6.5
Sources
- CVE-2021-38373 · CVE Program
- CVE-2021-38373 · NVD
- FIRST EPSS
- GHSA-rc8g-gfxp-864v · GitHub Advisory Database · CC BY 4.0
- CVE-2021-38373 · Red Hat security data · CC BY 4.0
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