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NVD / CVE Program· CNA mitre

CVE-2020-12243: In filter.c in slapd in OpenLDAP before 2.4.50, LDAP search filters with nested boolean expressions can result in denial of service (daemon

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: 4.7% (FIRST EPSS); higher than 91.8% 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-r1; openldap (Alpine:v3.11) 2.4.48-r2; openldap (Alpine:v3.12) 2.4.50-r0.

Low priority for now. Upgrade to openldap (Alpine:v3.10) 2.4.48-r1; openldap (Alpine:v3.11) 2.4.48-r2; openldap (Alpine:v3.12) 2.4.50-r0 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

In filter.c in slapd in OpenLDAP before 2.4.50, LDAP search filters with nested boolean expressions can result in denial of service (daemon crash).

HighCVSS 7.5 · v3.1—No exploit Fix available
Published
Apr 28, 2020
Updated
Oct 14, 2026
EPSS
4.7% · 91th 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 · 4.7%

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-2020-12243

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
opensuseleap
canonicalubuntu linux
netappcloud backup
netappsteelstore cloud integrated storage
netapph410c firmware
netapph410c
netapph300s firmware
netapph300s
netapph500s firmware
netapph500s

and 14 more

Affected versions

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

  • apple mac os x10.13.0 and later · before 10.13.6
  • apple mac os x10.15 and later · before 10.15.6
  • apple mac os x10.14.0 and later · before 10.14.6
  • apple mac os x10.13.6
  • apple mac os x10.14.6
  • broadcom brocade fabric operating systemall versions
  • canonical ubuntu linux12.04
  • canonical ubuntu linux14.04
  • canonical ubuntu linux16.04
  • canonical ubuntu linux18.04
  • canonical ubuntu linux19.10
  • canonical ubuntu linux20.04
  • debian debian linux10.0
  • debian debian linux8.0
  • debian debian linux9.0
  • netapp cloud backupall versions
  • netapp h300e firmwareall versions
  • netapp h300s firmwareall versions
  • netapp h410c firmwareall versions
  • netapp h410s firmwareall versions

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-r12.4.48-r1
Alpine:v3.11openldapbefore 2.4.48-r22.4.48-r2
Alpine:v3.12openldapbefore 2.4.50-r02.4.50-r0
Debian:10openldapbefore 2.4.47+dfsg-3+deb10u22.4.47+dfsg-3+deb10u2
Debian:12openldapbefore 2.4.50+dfsg-12.4.50+dfsg-1
Debian:8openldapbefore 2.4.40+dfsg-1+deb8u62.4.40+dfsg-1+deb8u6
Debian:9openldapbefore 2.4.44+dfsg-5+deb9u42.4.44+dfsg-5+deb9u4
openSUSE:Leap 15.1openldap2before 2.4.46-lp151.10.9.12.4.46-lp151.10.9.1
Red Hat:enterprise_linux:7::clientopenldapbefore 0:2.4.44-22.el70:2.4.44-22.el7
Red Hat:enterprise_linux:7::clientopenldap-clientsbefore 0:2.4.44-22.el70:2.4.44-22.el7
Red Hat:enterprise_linux:7::clientopenldap-debuginfobefore 0:2.4.44-22.el70:2.4.44-22.el7
Red Hat:enterprise_linux:7::clientopenldap-develbefore 0:2.4.44-22.el70:2.4.44-22.el7
Red Hat:enterprise_linux:7::clientopenldap-serversbefore 0:2.4.44-22.el70:2.4.44-22.el7
Red Hat:enterprise_linux:7::clientopenldap-servers-sqlbefore 0:2.4.44-22.el70:2.4.44-22.el7
SUSE:HPE Helion OpenStack 8openldap2before 2.4.41-18.68.12.4.41-18.68.1
SUSE:Linux Enterprise Module for Basesystem 15 SP1openldap2before 2.4.46-9.28.22.4.46-9.28.2
SUSE:Linux Enterprise Module for Legacy 12openldap2before 2.4.41-18.24.17.12.4.41-18.24.17.1
SUSE:Linux Enterprise Point of Sale 11 SP3openldap2before 2.4.26-0.74.9.12.4.26-0.74.9.1
SUSE:Linux Enterprise Point of Sale 11 SP3openldap2-clientbefore 2.4.26-0.74.9.12.4.26-0.74.9.1
SUSE:Linux Enterprise Server 11-SECURITYopenldap2-client-openssl1before 2.4.26-0.74.9.12.4.26-0.74.9.1
SUSE:Linux Enterprise Server for SAP Applications 12 SP1openldap2-clientbefore 2.4.41-18.24.17.12.4.41-18.24.17.1

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-2019-13565Jul 26, 2019 · An issue was discovered in OpenLDAP 2.x before 2.4.48.
    32Monitor
  • ← EarlierCVE-2014-8182Jan 2, 2020 · An off-by-one error leading to a crash was discovered in openldap 2.4 when processing DNS SRV messages.
    31Monitor
  • Later →CVE-2020-15719Jul 14, 2020 · libldap in certain third-party OpenLDAP packages has a certificate-validation flaw when the third-party package is asserting RFC6125 support
    17Monitor

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-r1 · Alpine:v3.10Package registry (OSV)
debian:openldap2.4.50+dfsg-1 · Debian:12Package registry (OSV)
opensuse:openldap22.4.46-lp151.10.9.1 · openSUSE:Leap 15.1Package registry (OSV)
red hat:openldap0:2.4.44-22.el7 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-clients0:2.4.44-22.el7 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-debuginfo0:2.4.44-22.el7 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-devel0:2.4.44-22.el7 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-servers0:2.4.44-22.el7 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
red hat:openldap-servers-sql0:2.4.44-22.el7 · Red Hat:enterprise_linux:7::clientPackage registry (OSV)
suse:openldap22.4.41-18.68.1 · SUSE:HPE Helion OpenStack 8Package registry (OSV)
suse:openldap2-client2.4.41-18.24.17.1 · SUSE:Linux Enterprise Server for SAP Applications 12 SP1Package registry (OSV)
suse:openldap2-client-openssl12.4.26-0.74.9.1 · 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.

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).

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-674 · Uncontrolled Recursion

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.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

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

References

Show all references (11 more)

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

All records