CVE-2026-103877CWE-502insecure-deserialization

CVE-2026-103877

Critical · published October 2, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
46.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00572 · 46.6th percentile
Weakness
CWE-502 · Deserialization of Untrusted Data
Published
2026-10-02T14:17Z
References (2)
https://lists.apache.org/thread.html/sys8l881blqfgoc3o724jl32bmjl8pvw · [email protected]http://www.openwall.com/lists/oss-security/2026/10/02/5 · af854a3a-2127-422b-91ae-364da2661108
EPSS history
Timeline
  • 04 OCT 03:27Z
    EPSS moved — → 0%
    epss
  • 02 OCT 10:08Z
    Apache Directory LDAP API: Unsafe loading of Java code from LDAP schema elements
    cvelistv5