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TI-2021-21535 Aliases CVE-2021-46853GHSA-v9q2-jxcm-rm4c

Alpine before 2.25 allows remote attackers to cause a denial of service (application…

Priority LOW 29CWE-367Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.

Summary

Alpine before 2.25 allows remote attackers to cause a denial of service (application crash) when LIST or LSUB is sent before STARTTLS.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01147 66th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

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:alpine_project:alpine:*:*:*:*:*:*:*:*before 2.25VulnerableAlpine Project
  • cpe:2.3:a:alpine_project:alpine:*:*:*:*:*:*:*:* Versions before 2.25 Vulnerable ·Alpine Project

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-46853
  2. 2026-10-03 Alias added: GHSA-v9q2-jxcm-rm4c

References

  • TI-2022-07606 URL access filters bypass in Alpine CVSS 3.1HIGH 7.5
  • TI-2020-11740 Alpine before 2.23 silently proceeds to use an insecure connection after a /tls is sent… CVSS 3.1HIGH 7.5
  • TI-2022-07607 Authentication bypass in Alpine CVSS 3.1MEDIUM 6.5
  • TI-2021-15974 In Alpine before 2.25, untagged responses from an IMAP server are accepted before STARTTLS. CVSS 3.1MEDIUM 5.9

Sources