CVE-2020-25710 — A flaw was found in OpenLDAP in versions before 2.4.56. This flaw allows an attacker who sends a...
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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 2.7% (30-day exploitation probability)+13
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — bugzilla.redhat.com (NIST National Vulnerability Database)
- Documented patch — git.openldap.org (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Debian Debian Linux, Fedoraproject Fedora, Openldap OpenLDAP…).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Debian | Debian Linux | version 9.0 | Vulnerable | NIST National Vulnerability Database |
| Fedoraproject | Fedora | version 33 | Vulnerable | NIST National Vulnerability Database |
| Openldap | OpenLDAP | < 2.4.56 | Vulnerable | NIST National Vulnerability Database |
| Red Hat | Enterprise Linux | version 5.0version 6.0version 7.0 | Vulnerable | NIST National Vulnerability Database |
| Red Hat | Jboss Core Services | versions not specified by the source | Vulnerable | NIST National Vulnerability Database |
| Red Hat | Jboss Enterprise Application Platform | version 5.0.0 | Vulnerable | NIST National Vulnerability Database |
| Red Hat | Jboss Enterprise Web Server | version 2.0.0 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.5 | CVSS 3.1 | High | 3.9 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
| 5.0 | CVSS 2.0 | Medium | 10.0 | 2.9 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 2.73%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Fix documented
- Affected products added · openldap/openldap, redhat/jboss core services, redhat/jboss enterprise application platform, redhat/jboss enterprise web
- CVSS changed · 7.5
- Source status changed · → Modified
- Record created in this database
- 2021
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 14, 2026 – Oct 14, 2026
References
12 on the record
- git.openldap.org/openldap/openldap/-/commit/ab3915154e69920d480205b4bf5ccb2b391a0a1f
- bugzilla.redhat.com/show_bug.cgi
- lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b
- lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4
- lists.debian.org/debian-lts-announce/2020/12/msg00008.html
- nvd.nist.gov/vuln/detail/CVE-2020-25710
- cert-portal.siemens.com/productcert/html/ssa-398330.html
- www.debian.org/security/2020/dsa-4792
- lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b
- github.com/advisories/GHSA-8wg3-gqcw-9fq9
- lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4
- security.netapp.com/advisory/ntap-20210716-0003/
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-104046 Sssd: sssd: denial of service via incomplete identity provider authentication requests 9d
- Medium CVE-2026-104045 Sssd: sssd: denial of service via race condition in autofs responder 9d
- Medium CVE-2026-104047 Sssd: sssd: information disclosure via query injection in entra id lookups 9d
- High CVE-2026-104048 Sssd: sssd: authorization bypass via cross-domain username collision in hbac evaluation 9d
- High CVE-2026-102558 Libsoup: libsoup: heap buffer overflow during websocket receive-buffer growth 16d
- Critical CVE-2026-102560 Libsoup: libsoup: heap buffer overflow during outgoing permessage-deflate buffer growth 16d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CISA SSVC assessment.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2020-25710 is "A flaw was found in OpenLDAP in versions before 2.4.56. This flaw allows an attacker who sends a...", rated High. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 2.73% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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