What’s Vulnerable › Vulnerabilities

CVE-2025-9640: Samba: vfs_streams_xattr uninitialized memory write possible

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-10-15 · updated 2026-10-18
• Weakness: CWE-908

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.

Affected products

• Red Hat OpenShift Container Platform 4.18: all versions
• Red Hat Enterprise Linux 10: all versions
• Red Hat Enterprise Linux 6: all versions
• Red Hat Enterprise Linux 7: all versions
• Red Hat Enterprise Linux 8: all versions
• Red Hat Enterprise Linux 9: all versions

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

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