CVE-2026-78323Network attack vector

TLS trust bypass via ignored NSS trust flags

Published Aug 24, 2026 · Updated Aug 24, 2026

Improper certificate validation in Red Hat JSS on Certificate System and RHEL 9 and 10 allows man-in-the-middle attackers to forge TLS certificates. JSSTrustManager accepts CA certificates from the NSS database as trust anchors without checking for TRUSTED_CA flags. Exploitation requires a PKI client connection using this trust manager with certificate revocation verification disabled; the default TomcatJSS server path is unaffected.

CVSS severity6.5
Medium
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper certificate validation in Red Hat JSS on Certificate System and RHEL 9 and 10 allows man-in-the-middle attackers to forge TLS certificates. JSSTrustManager accepts CA certificates from the NSS database as trust anchors without checking for TRUSTED_CA flags. Exploitation requires a PKI client connection using this trust manager with certificate revocation verification disabled; the default TomcatJSS server path is unaffected.

The record

CVE
CVE-2026-78323
Published
Aug 24, 2026
Updated
Aug 24, 2026
Vendor
389 Directory Server
Product
Red Hat Certificate System
Classifications
CWE-295, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 24, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

389 Directory Server · Red Hat Certificate SystemAffected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 10Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.

Published CVSS scores

6.5Red HatCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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