CVE-2026-13608 PUBLISHED

OpenLDAP SASL authentication bypass

Assigner: curl
Reserved: 29.06.2026 Published: 06.09.2026 Updated: 06.09.2026

A flaw in the libcurl SASL negotiation for LDAP authentication allows an incomplete handshake sequence to be misinterpreted as a successful cryptographic verification. An attacker executing a Man-in-the-Middle (MITM) attack can inject a premature or shortcut response that bypasses complete peer validation.

Product Status

Vendor curl
Product curl
Versions Default: unaffected
  • affected from 8.21.0 to 8.21.0 (incl.)
  • affected from 8.20.0 to 8.20.0 (incl.)
  • affected from 8.19.0 to 8.19.0 (incl.)
  • affected from 8.18.0 to 8.18.0 (incl.)
  • affected from 8.17.0 to 8.17.0 (incl.)
  • affected from 8.16.0 to 8.16.0 (incl.)
  • affected from 8.15.0 to 8.15.0 (incl.)
  • affected from 8.14.1 to 8.14.1 (incl.)
  • affected from 8.14.0 to 8.14.0 (incl.)
  • affected from 8.13.0 to 8.13.0 (incl.)
  • affected from 8.12.1 to 8.12.1 (incl.)
  • affected from 8.12.0 to 8.12.0 (incl.)
  • affected from 8.11.1 to 8.11.1 (incl.)
  • affected from 8.11.0 to 8.11.0 (incl.)
  • affected from 8.10.1 to 8.10.1 (incl.)
  • affected from 8.10.0 to 8.10.0 (incl.)
  • affected from 8.9.1 to 8.9.1 (incl.)
  • affected from 8.9.0 to 8.9.0 (incl.)
  • affected from 8.8.0 to 8.8.0 (incl.)
  • affected from 8.7.1 to 8.7.1 (incl.)
  • affected from 8.7.0 to 8.7.0 (incl.)
  • affected from 8.6.0 to 8.6.0 (incl.)
  • affected from 8.5.0 to 8.5.0 (incl.)
  • affected from 8.4.0 to 8.4.0 (incl.)
  • affected from 8.3.0 to 8.3.0 (incl.)
  • affected from 8.2.1 to 8.2.1 (incl.)
  • affected from 8.2.0 to 8.2.0 (incl.)
  • affected from 8.1.2 to 8.1.2 (incl.)
  • affected from 8.1.1 to 8.1.1 (incl.)
  • affected from 8.1.0 to 8.1.0 (incl.)
  • affected from 8.0.1 to 8.0.1 (incl.)
  • affected from 8.0.0 to 8.0.0 (incl.)
  • affected from 7.88.1 to 7.88.1 (incl.)
  • affected from 7.88.0 to 7.88.0 (incl.)
  • affected from 7.87.0 to 7.87.0 (incl.)
  • affected from 7.86.0 to 7.86.0 (incl.)
  • affected from 7.85.0 to 7.85.0 (incl.)
  • affected from 7.84.0 to 7.84.0 (incl.)
  • affected from 7.83.1 to 7.83.1 (incl.)
  • affected from 7.83.0 to 7.83.0 (incl.)
  • affected from 7.82.0 to 7.82.0 (incl.)

Credits

  • Eunsoo Kim (Autonomous Code Security team at Microsoft) finder
  • Eunsoo Kim remediation developer

References

Problem Types

  • CWE-923 Improper Restriction of Communication Channel to Intended Endpoints