What’s Vulnerable › Vulnerabilities

CVE-2021-33900: StartTLS and SASL confidentiality protection bypass

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.8% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-07-26 · updated 2026-06-17
• Weakness: CWE-311

Description

While investigating DIRSTUDIO-1219 it was noticed that configured StartTLS encryption was not applied when any SASL authentication mechanism (DIGEST-MD5, GSSAPI) was used. While investigating DIRSTUDIO-1220 it was noticed that any configured SASL confidentiality layer was not applied. This issue affects Apache Directory Studio version 2.0.0.v20210213-M16 and prior versions.

Affected products

• Apache Software Foundation Apache Directory Studio: through 1.5.3; 2.0.0-milestone1, 2.0.0-milestone10, 2.0.0-milestone11, 2.0.0-milestone12, 2.0.0-milestone13, 2.0.0-milestone14 (+10)

References

• https://lists.apache.org/thread.html/rb1dbcc43a5b406e45d335343a1704f4233de613140a01929d102fdc9%40%3Cusers.directory.apache.org%3E
• https://lists.apache.org/thread.html/rb1dbcc43a5b406e45d335343a1704f4233de613140a01929d102fdc9%40%3Cusers.directory.apache.org%3E

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