CVE-2025-59154

MEDIUM
Published Sep 15, 2025 Modified Apr 15, 2026 CWE-290

Description

Openfire is an XMPP server licensed under the Open Source Apache License. Openfire’s SASL EXTERNAL mechanism for client TLS authentication contains a vulnerability in how it extracts user identities from X.509 certificates. Instead of parsing the structured ASN.1 data, the code calls X509Certificate.getSubjectDN().getName() and applies a regex to look for CN=. This method produces a provider-dependent string that does not escape special characters. In SunJSSE (sun.security.x509.X500Name), for example, commas and equals signs inside attribute values are not escaped. As a result, a malicious certificate can embed CN= inside another attribute value (e.g. OU="CN=admin,"). The regex will incorrectly interpret this as a legitimate Common Name and extract admin. If SASL EXTERNAL is enabled and configured to map CNs to user accounts, this allows the attacker to impersonate another user. The fix is included in Openfire 5.0.2 and 5.1.0.

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CVSS v3.1 Score

5.9
MEDIUM
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:N

Weakness Type (CWE)

CWE-290 CWE-290

References

Frequently Asked Questions

What is CVE-2025-59154? +
Openfire is an XMPP server licensed under the Open Source Apache License. Openfire’s SASL EXTERNAL mechanism for client TLS authentication contains a vulnerability in how it extracts user identities from X.509 certificates. Instead of parsing the structured ASN.1 data, the code calls X509Certificate.getSubjectDN().getName() and applies a regex to look for CN=. This method produces a provider-dependent string that does not escape special characters. In SunJSSE (sun.security.x509.X500Name), for example, commas and equals signs inside attribute values are not escaped. As a result, a malicious certificate can embed CN= inside another attribute value (e.g. OU="CN=admin,"). The regex will incorrectly interpret this as a legitimate Common Name and extract admin. If SASL EXTERNAL is enabled and configured to map CNs to user accounts, this allows the attacker to impersonate another user. The fix is included in Openfire 5.0.2 and 5.1.0. It has a CVSS v3.1 base score of 5.9 (MEDIUM).
How severe is CVE-2025-59154? +
CVE-2025-59154 has a CVSS v3.1 score of 5.9 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
How do I check if I'm vulnerable to CVE-2025-59154? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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