CVE-2025-9640
published 2025-10-15CVE-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…
PriorityP421medium4.3CVSS 3.1
AVNACLPRLUINSUCLINAN
EPSS
0.43%
35.3th percentile
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
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | samba | < samba 2:4.17.12+dfsg-0+deb12u3 (bookworm) | samba 2:4.17.12+dfsg-0+deb12u3 (bookworm) |
| samba | samba | >= 0 < 2:4.13.13+dfsg-1~deb11u7 | 2:4.13.13+dfsg-1~deb11u7 |
| samba | samba | >= 0 < 2:4.17.12+dfsg-0+deb12u3 | 2:4.17.12+dfsg-0+deb12u3 |
| samba | samba | >= 0 < 2:4.22.6+dfsg-0+deb13u1 | 2:4.22.6+dfsg-0+deb13u1 |
| samba | samba | >= 0 < 2:4.23.2+dfsg-1 | 2:4.23.2+dfsg-1 |
| samba | samba | >= 0 < 2:4.15.13+dfsg-0ubuntu1.10 | 2:4.15.13+dfsg-0ubuntu1.10 |
| samba | samba | >= 0 < 2:4.19.5+dfsg-4ubuntu9.4 | 2:4.19.5+dfsg-4ubuntu9.4 |
| samba | samba | >= 0 < 2:4.22.3+dfsg-4ubuntu2.1 | 2:4.22.3+dfsg-4ubuntu2.1 |
| samba | samba | >= 0 < 2:4.3.11+dfsg-0ubuntu0.14.04.20+esm15 | 2:4.3.11+dfsg-0ubuntu0.14.04.20+esm15 |
| samba | samba | >= 0 < 2:4.3.11+dfsg-0ubuntu0.16.04.34+esm4 | 2:4.3.11+dfsg-0ubuntu0.16.04.34+esm4 |
| samba | samba | >= 0 < 2:4.7.6+dfsg~ubuntu-0ubuntu2.29+esm3 | 2:4.7.6+dfsg~ubuntu-0ubuntu2.29+esm3 |
| samba | samba | >= 0 < 2:4.15.13+dfsg-0ubuntu0.20.04.8+esm1 | 2:4.15.13+dfsg-0ubuntu0.20.04.8+esm1 |
CVSS provenance
nvdv3.14.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
osv10.0CRITICAL
vendor_ubuntu10.0CRITICAL
vendor_debian4.3MEDIUM
vendor_redhat4.3MEDIUM
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OSV
samba vulnerabilities
osv·2025-10-20·CVSS 10.0
CVE-2025-9640 [CRITICAL] samba vulnerabilities
samba vulnerabilities
USN-7826-1 fixed vulnerabilities in Samba. This update provides the
corresponding update for Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu
18.04 LTS and Ubuntu 20.04 LTS.
Original advisory details:
Andrew Walker discovered that Samba incorrectly initialized memory in the
vfs_streams_xattr module. An authenticated attacker could possibly use this
issue to obtain sensitive information. (CVE-2025-9640)
Igor Morgenstern discovered that Samba incorrectly handled names passed to
the WINS hook program. An attacker could possibly use this issue to execute
arbitrary code. (CVE-2025-10230)
OSV
samba vulnerabilities
osv·2025-10-16·CVSS 10.0
CVE-2025-9640 [CRITICAL] samba vulnerabilities
samba vulnerabilities
Andrew Walker discovered that Samba incorrectly initialized memory in the
vfs_streams_xattr module. An authenticated attacker could possibly use this
issue to obtain sensitive information. (CVE-2025-9640)
Igor Morgenstern discovered that Samba incorrectly handled names passed to
the WINS hook program. An attacker could possibly use this issue to execute
arbitrary code. (CVE-2025-10230)
OSV
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
osv·2025-10-15·CVSS 4.3
CVE-2025-9640 [MEDIUM] 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
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.
GHSA
GHSA-w497-wqwx-v847: A flaw was found in Samba, in the vfs_streams_xattr module, where uninitialized heap memory could be written into alternate data streams
ghsa_unreviewed·2025-10-15
CVE-2025-9640 [MEDIUM] CWE-908 GHSA-w497-wqwx-v847: A flaw was found in Samba, in the vfs_streams_xattr module, where uninitialized heap memory could be written into alternate data streams
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.
Ubuntu
Samba vulnerabilities
vendor_ubuntu·2025-10-20·CVSS 10.0
CVE-2025-9640 [CRITICAL] Samba vulnerabilities
Title: Samba vulnerabilities
Summary: Several security issues were fixed in Samba.
USN-7826-1 fixed vulnerabilities in Samba. This update provides the
corresponding update for Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, Ubuntu
18.04 LTS and Ubuntu 20.04 LTS.
Original advisory details:
Andrew Walker discovered that Samba incorrectly initialized memory in the
vfs_streams_xattr module. An authenticated attacker could possibly use this
issue to obtain sensitive information. (CVE-2025-9640)
Igor Morgenstern discovered that Samba incorrectly handled names passed to
the WINS hook program. An attacker could possibly use this issue to execute
arbitrary code. (CVE-2025-10230)
Instructions: In general, a standard system update will make all the necessary changes.
Ubuntu
Samba vulnerabilities
vendor_ubuntu·2025-10-16·CVSS 10.0
CVE-2025-10230 [CRITICAL] Samba vulnerabilities
Title: Samba vulnerabilities
Summary: Several security issues were fixed in Samba.
Andrew Walker discovered that Samba incorrectly initialized memory in the
vfs_streams_xattr module. An authenticated attacker could possibly use this
issue to obtain sensitive information. (CVE-2025-9640)
Igor Morgenstern discovered that Samba incorrectly handled names passed to
the WINS hook program. An attacker could possibly use this issue to execute
arbitrary code. (CVE-2025-10230)
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
samba: vfs_streams_xattr uninitialized memory write possible
vendor_redhat·2025-10-15·CVSS 4.3
CVE-2025-9640 [MEDIUM] CWE-908 samba: vfs_streams_xattr uninitialized memory write possible
samba: vfs_streams_xattr uninitialized memory write possible
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.
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.
Statement: This vulnerability is rated Low because its exploitation scope and potential impact are tightly constrained. Technically, the flaw only allows
Debian
CVE-2025-9640: samba - A flaw was found in Samba, in the vfs_streams_xattr module, where uninitialized ...
vendor_debian·2025·CVSS 4.3
CVE-2025-9640 [MEDIUM] CVE-2025-9640: samba - A flaw was found in Samba, in the vfs_streams_xattr module, where uninitialized ...
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.
Scope: local
bookworm: resolved (fixed in 2:4.17.12+dfsg-0+deb12u3)
bullseye: resolved (fixed in 2:4.13.13+dfsg-1~deb11u7)
forky: resolved (fixed in 2:4.23.2+dfsg-1)
sid: resolved (fixed in 2:4.23.2+dfsg-1)
trixie: resolved (fixed in 2:4.22.6+dfsg-0+deb13u1)
No detection rules found.
No public exploits indexed.
https://access.redhat.com/security/cve/CVE-2025-9640https://bugzilla.redhat.com/show_bug.cgi?id=2391698https://www.samba.org/samba/history/security.htmlhttp://www.openwall.com/lists/oss-security/2025/10/15/2http://www.openwall.com/lists/oss-security/2025/10/16/2https://lists.debian.org/debian-lts-announce/2025/11/msg00027.html
2025-10-15
Published