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CVE-2018-21246 — Vulnerability in github.com/caddyserver/caddy —...

CRITICAL

Caddy vulnerable to Authentication Bypass due to mishandling of TLS client authentication

Published October 6, 2022Updated November 8, 2023Source: osv

Summary

Caddy before 0.10.13 mishandles TLS client authentication, as demonstrated by an authentication bypass caused by the lack of the StrictHostMatching mode.

Advisory Timeline

  • First published October 6, 2022 (1467 days ago).
  • Last revised November 8, 2023 — 397 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

Go
Update github.com/caddyserver/caddy to 0.10.13 or later
go get github.com/caddyserver/caddy@v0.10.13

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (1)

Affects 1 ecosystem: go (1).

PackageEcosystemAffectedFixed In
github.com/caddyserver/caddy
go
All versions0.10.13

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

  • CWE-287
    Improper AuthenticationMITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 9.8 score means for each attack dimension.

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Frequently Asked Questions

What is CVE-2018-21246?
Caddy vulnerable to Authentication Bypass due to mishandling of TLS client authentication This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 9.8/10).
How do I check if my project is affected by CVE-2018-21246?
CVE-2018-21246 affects github.com/caddyserver/caddy. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2018-21246 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score
9.8

Exploitation is straightforward and causes maximum impact. Patch immediately.

Also Known As

GHSA-gr7w-x2jp-3xgw
GO-2020-0043

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