Apache Directory LDAP API: Unsafe loading of Java code from LDAP schema elements
Summary
| CVE | CVE-2026-103877 |
|---|---|
| State | PUBLISHED |
| Assigner | apache |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-02 10:17:06 UTC |
| Updated | 2026-10-07 23:16:58 UTC |
| Description | Deserialization of Untrusted Data vulnerability in Apache Directory LDAP API. A rogue/compromised LDAP server (or pre-TLS MITM) can answer a client's loadSchema() subschema search with a schema object that contains a serialized Java class, allowing some potential RCE. This issue affects Apache Directory LDAP API: from 2.1.0 before 2.1.9. Users are recommended to upgrade to version 2.1.9, which fixes the issue. |
Risk And Classification
Primary CVSS: v3.1 9.8 CRITICAL from ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.003860000 probability, percentile 0.304990000 (date 2026-10-07)
Problem Types: CWE-502 | CWE-502 CWE-502 Deserialization of Untrusted Data
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 9.8 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 9.8 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Apache Software Foundation | Apache Directory LDAP API | affected 2.1.0 2.1.9 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| lists.apache.org/thread.html/sys8l881blqfgoc3o724jl32bmjl8pvw | [email protected] | lists.apache.org | |
| www.openwall.com/lists/oss-security/2026/10/02/5 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Claude Security (en)
CNA: The Apache Software Foundation (en)
There are currently no legacy QID mappings associated with this CVE.