Cyber Resilience

CVE-2026-27860

Published
27 March 2026
Modified
30 March 2026
CVSS Score v3.1 3.7
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS Score 0.0029 21th percentile
Risk Priority 32 floored blend · peak EPSS

Summary

CVE-2026-27860 is a low-severity LDAP Injection (CWE-90) vulnerability in Open Xchange (inferred from references). Its CVSS base score is 3.7 (Low).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 21th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

If auth_username_chars is empty, it is possible to inject arbitrary LDAP filter to Dovecot's LDAP authentication. This leads to potentially bypassing restrictions and allows probing of LDAP structure. Do not clear out auth_username_chars, or install fixed version. No publicly available…

more

exploits are known.

CWE(s)
CWE-90

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-40459Shared CWE-90
CVE-2026-1498Shared CWE-90
CVE-2024-56841Shared CWE-90
CVE-2026-25560Shared CWE-90
CVE-2025-27686Shared CWE-90
CVE-2024-27310Shared CWE-90
CVE-2023-6905Shared CWE-90
CVE-2026-58222Shared CWE-90
CVE-2026-45559Shared CWE-90
CVE-2026-39962Shared CWE-90

Affected Assets

Open Xchange
—
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.2.6

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover LDAP injection flaws through static analysis or crafted test cases.

SI-10 Information Input Validation good match

Input validation directly stops untrusted data from reaching an LDAP query builder without neutralization of special characters.

SA-8 Security and Privacy Engineering Principles partial match

Secure engineering principles require safe query construction and escaping that structurally prevents LDAP injection.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input neutralization and query parameterization to prevent LDAP injection.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development catches LDAP injection via dynamic analysis or fuzzing, but does not prevent it at the source.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle mandates input validation and query construction practices that directly prevent LDAP injection.

A.8.26 Application security requirements partial match
prevents

Application security requirements include explicit rules for safe construction of directory queries, mitigating LDAP injection.

A.8.28 Secure coding partial match
prevents

Secure coding standards require proper neutralization of LDAP special characters, directly eliminating this weakness.

A.8.27 Secure system architecture and engineering principles none match
mitigates

Secure architecture principles encourage safe query interfaces but do not prescribe the specific coding controls needed for LDAP injection.

A.8.3 Information access restriction none match
none

Information access restriction limits who can query LDAP but does not address how queries are built.

References