CVE-2025-9640 (CVSS 4.3)

Description

A flaw was found in Samba, in the vfs_streams_xattr module, where uninitialized heap memory could be written into alternate data streams. This allows an authenticated user to read residual memory content that may include sensitive data, resulting in an information disclosure vulnerability.

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CVSS v3.1 Score

4.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Weakness Type (CWE)

CWE-908 CWE-908

References

Other References

https://access.redhat.com/security/cve/CVE-2025-9640 https://bugzilla.redhat.com/show_bug.cgi?id=2391698 https://www.samba.org/samba/history/security.html http://www.openwall.com/lists/oss-security/2025/10/15/2 http://www.openwall.com/lists/oss-security/2025/10/16/2 https://lists.debian.org/debian-lts-announce/2025/11/msg00027.html

Frequently Asked Questions

What is CVE-2025-9640? +

A flaw was found in Samba, in the vfs_streams_xattr module, where uninitialized heap memory could be written into alternate data streams. This allows an authenticated user to read residual memory content that may include sensitive data, resulting in an information disclosure vulnerability. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2025-9640? +

CVE-2025-9640 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2025-9640? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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