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TI-2021-15977 Aliases CVE-2021-38373GHSA-rc8g-gfxp-864v

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

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:kde:kmail:19.12.3:*:*:*:*:*:*:*19.12.3VulnerableKDE
  • cpe:2.3:a:kde:kmail:19.12.3:*:*:*:*:*:*:* Versions 19.12.3 Vulnerable ·KDE

Remediation

No fixed version listed by the sources yet.

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 7AffectedNo fix planned: Out of support scope

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-38373
  2. 2026-10-03 Alias added: GHSA-rc8g-gfxp-864v

References

  • 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
See all 9 →

Sources