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NVD / CVE Program· CNA redhat

CVE-2020-25709: A flaw was found in OpenLDAP.

Noroxi assessment

Priority: Monitor (action score 31/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 3.4% (FIRST EPSS); higher than 89% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: openldap (Alpine:v3.10) 2.4.48-r2; openldap (Alpine:v3.11) 2.4.48-r3; openldap (Alpine:v3.12) 2.4.50-r1.
  • Mentioned 3 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to openldap (Alpine:v3.10) 2.4.48-r2; openldap (Alpine:v3.11) 2.4.48-r3; openldap (Alpine:v3.12) 2.4.50-r1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A flaw was found in OpenLDAP. This flaw allows an attacker who can send a malicious packet to be processed by OpenLDAP’s slapd server, to trigger an assertion failure. The highest threat from this vulnerability is to system availability.

HighCVSS 7.5 · v3.1—No exploit Fix available
Published
May 18, 2021
Updated
Oct 14, 2026
EPSS
3.4% · 89th percentile

Report tools

JSON

Action score

31

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 3.4%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2020-25709

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
openldapopenldap
debiandebian linux
applemac os x
applemacos
redhatjboss core services

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • apple mac os x10.14.0 and later · before 10.14.6
  • apple mac os x10.15 and later · before 10.15.7
  • apple mac os x10.14.6
  • apple mac os x10.15.7
  • apple macos11.0 and later · before 11.0.1
  • debian debian linux10.0
  • debian debian linux9.0
  • openldap openldapbefore 2.4.56
  • redhat jboss core servicesall versions

Versions reported by the vendor

Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.

  • n/a OpenLDAP

    • openldap 2.4.56affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Alpine:v3.10openldapbefore 2.4.48-r22.4.48-r2
Alpine:v3.11openldapbefore 2.4.48-r32.4.48-r3
Alpine:v3.12openldapbefore 2.4.50-r12.4.50-r1
Alpine:v3.13openldapbefore 2.4.56-r02.4.56-r0
Debian:10openldapbefore 2.4.47+dfsg-3+deb10u42.4.47+dfsg-3+deb10u4
Debian:12openldapbefore 2.4.56+dfsg-12.4.56+dfsg-1
Debian:9openldapbefore 2.4.44+dfsg-5+deb9u62.4.44+dfsg-5+deb9u6
openSUSE:Leap 15.1openldap2before 2.4.46-lp151.10.24.12.4.46-lp151.10.24.1
openSUSE:Leap 15.2openldap2before 2.4.46-lp152.14.15.12.4.46-lp152.14.15.1
Red Hat:enterprise_linux:7::clientopenldapbefore 0:2.4.44-25.el7_90:2.4.44-25.el7_9
Red Hat:enterprise_linux:7::clientopenldap-clientsbefore 0:2.4.44-25.el7_90:2.4.44-25.el7_9
Red Hat:enterprise_linux:7::clientopenldap-debuginfobefore 0:2.4.44-25.el7_90:2.4.44-25.el7_9
Red Hat:enterprise_linux:7::clientopenldap-develbefore 0:2.4.44-25.el7_90:2.4.44-25.el7_9
Red Hat:enterprise_linux:7::clientopenldap-serversbefore 0:2.4.44-25.el7_90:2.4.44-25.el7_9
Red Hat:enterprise_linux:7::clientopenldap-servers-sqlbefore 0:2.4.44-25.el7_90:2.4.44-25.el7_9
SUSE:Linux Enterprise Module for Basesystem 15 SP2openldap2before 2.4.46-9.45.12.4.46-9.45.1
SUSE:Linux Enterprise Module for Legacy 12openldap2before 2.4.41-18.24.26.12.4.41-18.24.26.1
SUSE:Linux Enterprise Server 11-SECURITYopenldap2-client-openssl1before 2.4.26-0.74.19.12.4.26-0.74.19.1
SUSE:Linux Enterprise Software Development Kit 12 SP5openldap2before 2.4.41-18.80.12.4.41-18.80.1

Same product

openldap: all records

Other highest-scoring records for the same primary product.

  • CVE-2022-29155In OpenLDAP 2.x before 2.5.12 and 2.6.x before 2.6.2, a SQL injection vulnerability exists in the experimental back-sql backend to slapd, vi
    58Plan
  • CVE-2020-36228An integer underflow was discovered in OpenLDAP before 2.4.57 leading to a slapd crash in the Certificate List Exact Assertion processing, r
    55Plan
  • CVE-2020-36221An integer underflow was discovered in OpenLDAP before 2.4.57 leading to slapd crashes in the Certificate Exact Assertion processing, result
    55Plan

Published before and after this one in the same product

  • ← EarlierCVE-2020-36230Jan 26, 2021 · A flaw was discovered in OpenLDAP before 2.4.57 leading in an assertion failure in slapd in the X.509 DN parsing in decode.c ber_next_elemen
    34Monitor
  • ← EarlierCVE-2021-27212Feb 14, 2021 · In OpenLDAP through 2.4.57 and 2.5.x through 2.5.1alpha, an assertion failure in slapd can occur in the issuerAndThisUpdateCheck function vi
    50Plan
  • Later →CVE-2020-25710May 28, 2021 · A flaw was found in OpenLDAP in versions before 2.4.56.
    31Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
alpine:openldap2.4.48-r2 · Alpine:v3.10Package registry (OSV)
debian:openldap2.4.56+dfsg-1 · Debian:12Package registry (OSV)
opensuse:openldap22.4.46-lp151.10.24.1 · openSUSE:Leap 15.1Package registry (OSV)
red hat:openldap0:2.4.44-25.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-clients0:2.4.44-25.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-debuginfo0:2.4.44-25.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-devel0:2.4.44-25.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-servers0:2.4.44-25.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-servers-sql0:2.4.44-25.el7_9 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
suse:openldap22.4.41-18.80.1 · SUSE:Linux Enterprise Software Development Kit 12 SP5Package registry (OSV)
suse:openldap2-client-openssl12.4.26-0.74.19.1 · SUSE:Linux Enterprise Server 11-SECURITYPackage registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-617 · Reachable Assertion

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (8 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records