CVE-2020-36229: A flaw was discovered in ldap_X509dn2bv in OpenLDAP before 2.4.57 leading to a slapd crash in the X.509 DN parsing in ad_keystring, resultin
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: 4.3% (FIRST EPSS); higher than 91.2% 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:v3.13) 2.4.57-r0; openldap (Debian:10) 2.4.47+dfsg-3+deb10u5; openldap (Debian:12) 2.4.57+dfsg-1.
- Mentioned 2 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to openldap (Alpine:v3.13) 2.4.57-r0; openldap (Debian:10) 2.4.47+dfsg-3+deb10u5; openldap (Debian:12) 2.4.57+dfsg-1 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 discovered in ldap_X509dn2bv in OpenLDAP before 2.4.57 leading to a slapd crash in the X.509 DN parsing in ad_keystring, resulting in denial of service.
- Published
- Jan 26, 2021
- Updated
- Oct 14, 2026
- EPSS
- 4.3% · 91th percentile
- CWE
- CWE-843
Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 4.3%
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.
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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.
We use this product, ask for helpAffected 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.
| Vendor | Product | CPE |
|---|---|---|
| openldap | openldap | cpe:2.3:a:openldap:openldap |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| apple | mac os x | cpe:2.3:o:apple:mac_os_x |
| apple | macos | cpe:2.3:o:apple:macos |
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 x10.14.6
- apple macos11.1 and later · before 11.4
- debian debian linux10.0
- debian debian linux9.0
- openldap openldapbefore 2.4.57
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Alpine:v3.13 | openldap | before 2.4.57-r0 | 2.4.57-r0 |
| Debian:10 | openldap | before 2.4.47+dfsg-3+deb10u5 | 2.4.47+dfsg-3+deb10u5 |
| Debian:12 | openldap | before 2.4.57+dfsg-1 | 2.4.57+dfsg-1 |
| Debian:9 | openldap | before 2.4.44+dfsg-5+deb9u7 | 2.4.44+dfsg-5+deb9u7 |
| openSUSE:Leap 15.2 | openldap2 | before 2.4.46-lp152.14.18.1 | 2.4.46-lp152.14.18.1 |
| SUSE:HPE Helion OpenStack 8 | openldap2 | before 2.4.41-18.83.1 | 2.4.41-18.83.1 |
| SUSE:Linux Enterprise Module for Basesystem 15 SP2 | openldap2 | before 2.4.46-9.48.1 | 2.4.46-9.48.1 |
| SUSE:Linux Enterprise Module for Legacy 12 | openldap2 | before 2.4.41-39.1 | 2.4.41-39.1 |
| SUSE:Linux Enterprise Point of Sale 11 SP3 | openldap2 | before 2.4.26-0.74.26.1 | 2.4.26-0.74.26.1 |
| SUSE:Linux Enterprise Point of Sale 11 SP3 | openldap2-client | before 2.4.26-0.74.26.1 | 2.4.26-0.74.26.1 |
| SUSE:Linux Enterprise Server 11-SECURITY | openldap2-client-openssl1 | before 2.4.26-0.74.26.1 | 2.4.26-0.74.26.1 |
Same product
openldap: all recordsOther 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, vi58Plan
- 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, r55Plan
- CVE-2020-36221An integer underflow was discovered in OpenLDAP before 2.4.57 leading to slapd crashes in the Certificate Exact Assertion processing, result55Plan
Published before and after this one in the same product
- ← EarlierCVE-2020-36226Jan 26, 2021 · A flaw was discovered in OpenLDAP before 2.4.57 leading to a memch->bv_len miscalculation and slapd crash in the saslAuthzTo processing, res31Monitor
- ← EarlierCVE-2020-36227Jan 26, 2021 · A flaw was discovered in OpenLDAP before 2.4.57 leading to an infinite loop in slapd with the cancel_extop Cancel operation, resulting in de53Plan
- Later →CVE-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_elemen34Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| alpine:openldap | 2.4.57-r0 · Alpine:v3.13 | Package registry (OSV) |
| debian:openldap | 2.4.57+dfsg-1 · Debian:12 | Package registry (OSV) |
| opensuse:openldap2 | 2.4.46-lp152.14.18.1 · openSUSE:Leap 15.2 | Package registry (OSV) |
| suse:openldap2 | 2.4.41-39.1 · SUSE:Linux Enterprise Module for Legacy 12 | Package registry (OSV) |
| suse:openldap2-client | 2.4.26-0.74.26.1 · SUSE:Linux Enterprise Point of Sale 11 SP3 | Package registry (OSV) |
| suse:openldap2-client-openssl1 | 2.4.26-0.74.26.1 · SUSE:Linux Enterprise Server 11-SECURITY | Package 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 researchersFinders, 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.
- TR-21-0973 · Dec 8, 2021(Hitachi Güvenlik Zafiyeti)
- TR-21-0113 · Feb 8, 2021(OpenLDAP Güvenlik Zafiyeti)
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-843 · Access of Resource Using Incompatible Type ('Type Confusion')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
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (14 more)Show less
- seclists.org/fulldisclosure/2021/May/65
- seclists.org/fulldisclosure/2021/May/70
- bugs.openldap.org/show_bug.cgi?id=9425
- git.openldap.org/openldap/openldap/-/commit/4bdfffd2889c0c5cdf58bebafbdc8fce4bb2bff0
- git.openldap.org/openldap/openldap/-/tags/OPENLDAP_REL_ENG_2_4_57
- lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- lists.debian.org/debian-lts-announce/2021/02/msg00005.html
- security.netapp.com/advisory/ntap-20210226-0002/
- support.apple.com/kb/HT212529
- support.apple.com/kb/HT212530
- support.apple.com/kb/HT212531
- www.debian.org/security/2021/dsa-4845
- cert-portal.siemens.com/productcert/html/ssa-398330.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.