CVE-2020-36228
CVE-2020-36228 is a high-severity vulnerability in Openldap with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 83% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-191.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 83% (100th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-191
- Affected product: Openldap
- Published:
- Last modified:
Description
An integer underflow was discovered in OpenLDAP before 2.4.57 leading to a slapd crash in the Certificate List Exact Assertion processing, resulting in denial of service.
Frequently asked questions
- What is CVE-2020-36228?
- An integer underflow was discovered in OpenLDAP before 2.4.57 leading to a slapd crash in the Certificate List Exact Assertion processing, resulting in denial of service.
- How severe is CVE-2020-36228?
- CVE-2020-36228 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2020-36228 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 83% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-36228?
- CVE-2020-36228 primarily affects Openldap. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-36228?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-36228 published?
- CVE-2020-36228 was published on 2021-01-26 and last updated on 2026-06-17.
References
- http://seclists.org/fulldisclosure/2021/May/64
- http://seclists.org/fulldisclosure/2021/May/65
- http://seclists.org/fulldisclosure/2021/May/70
- https://bugs.openldap.org/show_bug.cgi?id=9427
- https://git.openldap.org/openldap/openldap/-/commit/91dccd25c347733b365adc74cb07d074512ed5ad
- https://git.openldap.org/openldap/openldap/-/tags/OPENLDAP_REL_ENG_2_4_57
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2021/02/msg00005.html
- https://security.netapp.com/advisory/ntap-20210226-0002/
- https://support.apple.com/kb/HT212529
- https://support.apple.com/kb/HT212530
- https://support.apple.com/kb/HT212531
- https://www.debian.org/security/2021/dsa-4845
Affected products (4)
- cpe:2.3:a:openldap:openldap:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
- cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
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