MISP: Improper Neutralization of Special Elements used in an LDAP Query
CVE-2026-39962 is a critical-severity improper neutralization of special elements used in an LDAP query vulnerability in MISP, with a CVSS 3.1 base score of 9.6 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected MISP versions: < 2.5.36. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.35% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of MISP you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.8 | High | CNA (github.com) |
| CVSS 3.1 | 9.6 | Critical | NVD |
Official description
MISP is an open source threat intelligence and sharing platform. Prior to 2.5.36, improper neutralization of special elements in an LDAP query in ApacheAuthenticate.php allows LDAP injection via an unsanitized username value when ApacheAuthenticate.apacheEnv is configured to use a user-controlled server variable instead of REMOTE_USER (such as in certain proxy setups). An attacker able to control that value can manipulate the LDAP search filter and potentially bypass authentication constraints or cause unauthorized LDAP queries. This vulnerability is fixed in 2.5.36.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements used in an LDAP Query
The product constructs all or part of an LDAP query using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended LDAP query when it is sent to a downstream component.
More Improper Neutralization of Special Elements used in an LDAP Query vulnerabilities (CWE-90)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in MISP
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
Recent Improper Neutralization of Special Elements used in an LDAP Query vulnerabilities
- 8.2 High severity
- 7.5 High severity
- 7.5 High severity
- 9.8 Critical severity
- 8.8 High severity
- 9.8 Critical severity
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