Deserialization of Untrusted Data vulnerability in Apache Directory LDAP API. (CVE-2026-103877)
A deserialization of untrusted data vulnerability exists in Apache Directory LDAP API versions from 2.1.0 before 2.1.9. A rogue or compromised LDAP server, or a man-in-the-middle before TLS encryption, can respond to a client's loadSchema() subschema search with a schema object containing a serialized Java class. This can potentially lead to remote code execution. The issue is fixed in version 2.1.9.
AI Analysis
Technical Summary
The Apache Directory LDAP API suffers from a deserialization of untrusted data vulnerability (CWE-502) in versions 2.1.0 up to but not including 2.1.9. An attacker controlling or intercepting LDAP server responses can supply malicious serialized Java objects during the loadSchema() subschema search, which the client deserializes. This may allow remote code execution on the client side. The vulnerability is addressed by upgrading to version 2.1.9.
Potential Impact
If exploited, this vulnerability could allow an attacker to execute arbitrary code on a client using the affected LDAP API by supplying malicious serialized objects. This requires control over or interception of the LDAP server responses, such as a rogue LDAP server or a man-in-the-middle attack before TLS is established.
Mitigation Recommendations
Users should upgrade to Apache Directory LDAP API version 2.1.9 or later, which contains the fix for this vulnerability. No other mitigation or temporary workaround is indicated.
Deserialization of Untrusted Data vulnerability in Apache Directory LDAP API. (CVE-2026-103877)
Description
A deserialization of untrusted data vulnerability exists in Apache Directory LDAP API versions from 2.1.0 before 2.1.9. A rogue or compromised LDAP server, or a man-in-the-middle before TLS encryption, can respond to a client's loadSchema() subschema search with a schema object containing a serialized Java class. This can potentially lead to remote code execution. The issue is fixed in version 2.1.9.
Affected software
pkg:maven/org.apache.directory.api/api-ldap-apiRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Apache Directory LDAP API suffers from a deserialization of untrusted data vulnerability (CWE-502) in versions 2.1.0 up to but not including 2.1.9. An attacker controlling or intercepting LDAP server responses can supply malicious serialized Java objects during the loadSchema() subschema search, which the client deserializes. This may allow remote code execution on the client side. The vulnerability is addressed by upgrading to version 2.1.9.
Potential Impact
If exploited, this vulnerability could allow an attacker to execute arbitrary code on a client using the affected LDAP API by supplying malicious serialized objects. This requires control over or interception of the LDAP server responses, such as a rogue LDAP server or a man-in-the-middle attack before TLS is established.
Mitigation Recommendations
Users should upgrade to Apache Directory LDAP API version 2.1.9 or later, which contains the fix for this vulnerability. No other mitigation or temporary workaround is indicated.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-v496-rffp-c5q7
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-103877"]
- State
- PUBLISHED
Threat ID: 6abfee9ca43b0b3b89e551a7
Added to database: 10/02/2026, 17:49:16 UTC
Last enriched: 10/02/2026, 18:03:36 UTC
Last updated: 10/02/2026, 19:45:56 UTC
Views: 2
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