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Fencer Intel
high 8.5

CVE-2026-35563 json

Apache Directory LDAP API: LDAP client implementation does not verify if the server certificate matches the intended LDAP hostname

published 5mo ago modified 3mo ago also EUVD-2026-33569 , GHSA-85rw-g4f4-jprr

cvss
8.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 7%
public exploits
0
none known

Summary

It was identified that the LDAP client implementation in version 2.1.7 does not verify if the server certificate matches the intended LDAP hostname. While the underlying code validates the certificate chain against a trusted authority, the absence of endpoint identification allows a valid certificate issued for an entirely unrelated host to be improperly accepted. This oversight leaves the connection highly vulnerable to server impersonation and complete connection compromise.

The root cause of this vulnerability lies in the incomplete TLS server identity verification within the LDAP client implementation.

The attacker requires MITM capability on the network to exploit this vulnerability. This attacker must be able to present a certificate trusted by the client's configured trust store.

The hostname verification has been enforced in the new version of the LDAP API

Patch / fix

  • maven org.apache.directory.api:api-ldap-client-api 2.1.8

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
5mo ago

Exploit prediction

0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 4.0 8.8 CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:L/SA:L
CNA 4.0 8.8 CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:H/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 8.5 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
maven org.apache.directory.api:api-ldap-client-api
>=2.0.0, <2.1.8
2.1.8

Affected products

  • Apache Software Foundation Apache Directory LDAP API

Classification

Weakness
  • CWE-297 Improper Validation of Certificate with Host Mismatch

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.