7.5
HIGH CVSS 3.1
CVE-2026-103880
Apache Directory LDAP API: Denial of service via excessive bcrypt cost factor in stored passwords
Description

Asymmetric Resource Consumption vulnerability in Apache Directory LDAP API. Storing a password using the bcrypt algorithm with a high force like 30 in a LDAP server that supports this algorithm will cause the server CPU to  run for hours checking the credentials. A bounded cost should be enforced to avoid a server DOS. 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.

INFO

Published Date :

Oct. 2, 2026, 10:17 a.m.

Last Modified :

Oct. 5, 2026, 7:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-103880 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Apache directory_ldap_api
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH 134c704f-9b21-4f2e-91b3-4a467353bcc0
Solution
Upgrade to Apache Directory LDAP API version 2.1.9 to fix the denial of service vulnerability.
  • Upgrade Apache Directory LDAP API to version 2.1.9.
  • Enforce a bounded cost for bcrypt operations.
  • Monitor CPU usage during credential checks.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-103880.

URL Resource
https://lists.apache.org/thread.html/39q63m54v9go6xj7pqj7q18c3szn9go4
http://www.openwall.com/lists/oss-security/2026/10/02/7
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-103880 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-103880 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-103880 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-103880 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Oct. 05, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added SSVC {'id': 'CVE-2026-103880', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-10-05T18:46:46.577864Z'}
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Oct. 02, 2026

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2026/10/02/7
  • New CVE Received by [email protected]

    Oct. 02, 2026

    Action Type Old Value New Value
    Added Description Asymmetric Resource Consumption vulnerability in Apache Directory LDAP API. Storing a password using the bcrypt algorithm with a high force like 30 in a LDAP server that supports this algorithm will cause the server CPU to  run for hours checking the credentials. A bounded cost should be enforced to avoid a server DOS. 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.
    Added CWE CWE-405
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/103xxx/CVE-2026-103880.json">CVE-2026-103880</a>
    Added Reference https://lists.apache.org/thread.html/39q63m54v9go6xj7pqj7q18c3szn9go4
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.