CVE-2026-9648
CVE-2026-9648
Description
The crypton-x509-validation Haskell library fails to enforce X.509 NameConstraints, allowing TLS clients to accept certificates whose Subject Alternative Names fall outside the issuing CA’s permitted subtrees. This oversight enables an attacker who compromises a name-constrained sub-CA to impersonate domains beyond its intended scope.
INFO
Published Date :
June 11, 2026, 4:16 p.m.
Last Modified :
June 11, 2026, 5:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-9648
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Update the crypton-x509-validation library to the latest version.
- Verify NameConstraints enforcement in TLS client configurations.
- Reissue certificates if they were affected by the vulnerability.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-9648.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-9648 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-9648
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-9648 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-9648 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 11, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N -
New CVE Received by [email protected]
Jun. 11, 2026
Action Type Old Value New Value Added Description The crypton-x509-validation Haskell library fails to enforce X.509 NameConstraints, allowing TLS clients to accept certificates whose Subject Alternative Names fall outside the issuing CA’s permitted subtrees. This oversight enables an attacker who compromises a name-constrained sub-CA to impersonate domains beyond its intended scope. Added Reference https://github.com/haskell/security-advisories/pull/332 Added Reference https://github.com/kazu-yamamoto/crypton-certificate/pull/30 Added Reference https://github.com/kazu-yamamoto/crypton-certificate/pull/30/changes/f4b77edf6ead77f4a886da40e41eab20f0180e39 Added Reference https://hackage.haskell.org/package/crypton-x509-validation-1.9.1/revisions/ -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Jun. 11, 2026
Action Type Old Value New Value Added Reference https://www.kb.cert.org/vuls/id/862559