CVE-2023-4091
published 2023-11-03CVE-2023-4091: A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module…
PriorityP341medium6.5CVSS 3.1
AVNACLPRLUINSUCNIHAN
EPSS
1.17%
64.0th percentile
A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module "acl_xattr" is configured with "acl_xattr:ignore system acls = yes". The SMB protocol allows opening files when the client requests read-only access but then implicitly truncates the opened file to 0 bytes if the client specifies a separate OVERWRITE create disposition request. The issue arises in configurations that bypass kernel file system permissions checks, relying solely on Samba's permissions.
Affected
16 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | samba | < samba 2:4.17.12+dfsg-0+deb12u1 (bookworm) | samba 2:4.17.12+dfsg-0+deb12u1 (bookworm) |
| fedoraproject | fedora | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux_eus | — | — |
| redhat | storage | — | — |
| samba | samba | < 4.17.12 | 4.17.12 |
| samba | samba | >= 0 < 2:4.13.13+dfsg-1~deb11u6 | 2:4.13.13+dfsg-1~deb11u6 |
| samba | samba | >= 0 < 2:4.17.12+dfsg-0+deb12u1 | 2:4.17.12+dfsg-0+deb12u1 |
| samba | samba | >= 0 < 2:4.19.1+dfsg-1 | 2:4.19.1+dfsg-1 |
| samba | samba | >= 0 < 2:4.19.1+dfsg-1 | 2:4.19.1+dfsg-1 |
| samba | samba | >= 0 < 2:4.15.13+dfsg-0ubuntu0.20.04.7 | 2:4.15.13+dfsg-0ubuntu0.20.04.7 |
| samba | samba | >= 0 < 2:4.15.13+dfsg-0ubuntu0.20.04.6 | 2:4.15.13+dfsg-0ubuntu0.20.04.6 |
| samba | samba | >= 0 < 2:4.15.13+dfsg-0ubuntu1.5 | 2:4.15.13+dfsg-0ubuntu1.5 |
| samba | samba | >= 0 < 2:4.18.6+dfsg-1ubuntu2.1 | 2:4.18.6+dfsg-1ubuntu2.1 |
| samba | samba | >= 4.18.0 < 4.18.8 | 4.18.8 |
| samba | samba | >= 4.19.0 < 4.19.1 | 4.19.1 |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
osv6.5MEDIUM
vendor_debian6.5MEDIUM
vendor_redhat6.5MEDIUM
vendor_ubuntu6.5MEDIUM
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GHSA
GHSA-f6jj-3gjw-frjm: A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS modul
ghsa_unreviewed·2023-11-03
CVE-2023-4091 [MEDIUM] CWE-276 GHSA-f6jj-3gjw-frjm: A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS modul
A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module "acl_xattr" is configured with "acl_xattr:ignore system acls = yes". The SMB protocol allows opening files when the client requests read-only access but then implicitly truncates the opened file to 0 bytes if the client specifies a separate OVERWRITE create disposition request. The issue arises in configurations that bypass kernel file system permissions checks, relying solely on Samba's permissions.
OSV
CVE-2023-4091: A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS modul
osv·2023-11-03·CVSS 6.5
CVE-2023-4091 [MEDIUM] CVE-2023-4091: A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS modul
A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module "acl_xattr" is configured with "acl_xattr:ignore system acls = yes". The SMB protocol allows opening files when the client requests read-only access but then implicitly truncates the opened file to 0 bytes if the client specifies a separate OVERWRITE create disposition request. The issue arises in configurations that bypass kernel file system permissions checks, relying solely on Samba's permissions.
OSV
samba vulnerabilities
osv·2023-10-17·CVSS 6.5
CVE-2023-4091 [MEDIUM] samba vulnerabilities
samba vulnerabilities
USN-6425-1 fixed vulnerabilities in Samba. This update provides the
corresponding updates for Ubuntu 23.10.
Original advisory details:
Sri Nagasubramanian discovered that the Samba acl_xattr VFS module
incorrectly handled read-only files. When Samba is configured to ignore
system ACLs, a remote attacker could possibly use this issue to truncate
read-only files. (CVE-2023-4091)
Andrew Bartlett discovered that Samba incorrectly handled the DirSync
control. A remote attacker with an RODC DC account could possibly use this
issue to obtain all domain secrets. (CVE-2023-4154)
Andrew Bartlett discovered that Samba incorrectly handled the rpcecho
development server. A remote attacker could possibly use this issue to
cause Samba to stop responding, resulting in a denial o
OSV
samba regression
osv·2023-10-11·CVSS 6.5
[MEDIUM] samba regression
samba regression
USN-6425-1 fixed vulnerabilities in Samba. Due to a build issue on Ubuntu
20.04 LTS, the update introduced regressions in macro handling and
possibly other functionality.
This update fixes the problem. We apologize for the inconvenience.
Original advisory details:
Sri Nagasubramanian discovered that the Samba acl_xattr VFS module
incorrectly handled read-only files. When Samba is configured to ignore
system ACLs, a remote attacker could possibly use this issue to truncate
read-only files. (CVE-2023-4091)
Andrew Bartlett discovered that Samba incorrectly handled the DirSync
control. A remote attacker with an RODC DC account could possibly use this
issue to obtain all domain secrets. (CVE-2023-4154)
Andrew Bartlett discovered that Samba incorrectly handled the rpcecho
OSV
samba vulnerabilities
osv·2023-10-10·CVSS 6.5
CVE-2023-4091 [MEDIUM] samba vulnerabilities
samba vulnerabilities
Sri Nagasubramanian discovered that the Samba acl_xattr VFS module
incorrectly handled read-only files. When Samba is configured to ignore
system ACLs, a remote attacker could possibly use this issue to truncate
read-only files. (CVE-2023-4091)
Andrew Bartlett discovered that Samba incorrectly handled the DirSync
control. A remote attacker with an RODC DC account could possibly use this
issue to obtain all domain secrets. (CVE-2023-4154)
Andrew Bartlett discovered that Samba incorrectly handled the rpcecho
development server. A remote attacker could possibly use this issue to
cause Samba to stop responding, resulting in a denial of service.
(CVE-2023-42669)
Kirin van der Veer discovered that Samba incorrectly handled certain RPC
service listeners. A remote attacke
Ubuntu
Samba vulnerabilities
vendor_ubuntu·2023-10-17·CVSS 6.5
CVE-2023-42669 [MEDIUM] Samba vulnerabilities
Title: Samba vulnerabilities
Summary: Several security issues were fixed in Samba.
USN-6425-1 fixed vulnerabilities in Samba. This update provides the
corresponding updates for Ubuntu 23.10.
Original advisory details:
Sri Nagasubramanian discovered that the Samba acl_xattr VFS module
incorrectly handled read-only files. When Samba is configured to ignore
system ACLs, a remote attacker could possibly use this issue to truncate
read-only files. (CVE-2023-4091)
Andrew Bartlett discovered that Samba incorrectly handled the DirSync
control. A remote attacker with an RODC DC account could possibly use this
issue to obtain all domain secrets. (CVE-2023-4154)
Andrew Bartlett discovered that Samba incorrectly handled the rpcecho
development server. A remote attacker could possibly use this is
Ubuntu
Samba regression
vendor_ubuntu·2023-10-11·CVSS 6.5
[MEDIUM] Samba regression
Title: Samba regression
Summary: USN-6425-1 introduced a regression in Samba.
USN-6425-1 fixed vulnerabilities in Samba. Due to a build issue on Ubuntu
20.04 LTS, the update introduced regressions in macro handling and
possibly other functionality.
This update fixes the problem. We apologize for the inconvenience.
Original advisory details:
Sri Nagasubramanian discovered that the Samba acl_xattr VFS module
incorrectly handled read-only files. When Samba is configured to ignore
system ACLs, a remote attacker could possibly use this issue to truncate
read-only files. (CVE-2023-4091)
Andrew Bartlett discovered that Samba incorrectly handled the DirSync
control. A remote attacker with an RODC DC account could possibly use this
issue to obtain all domain secrets. (CVE-2023-4154)
Andrew B
Red Hat
samba: SMB clients can truncate files with read-only permissions
vendor_redhat·2023-10-10·CVSS 6.5
CVE-2023-4091 [MEDIUM] CWE-276 samba: SMB clients can truncate files with read-only permissions
samba: SMB clients can truncate files with read-only permissions
A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module "acl_xattr" is configured with "acl_xattr:ignore system acls = yes". The SMB protocol allows opening files when the client requests read-only access but then implicitly truncates the opened file to 0 bytes if the client specifies a separate OVERWRITE create disposition request. The issue arises in configurations that bypass kernel file system permissions checks, relying solely on Samba's permissions.
A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module "acl_xattr" is configured
Ubuntu
Samba vulnerabilities
vendor_ubuntu·2023-10-10·CVSS 6.5
CVE-2023-4091 [MEDIUM] Samba vulnerabilities
Title: Samba vulnerabilities
Summary: Several security issues were fixed in Samba.
Sri Nagasubramanian discovered that the Samba acl_xattr VFS module
incorrectly handled read-only files. When Samba is configured to ignore
system ACLs, a remote attacker could possibly use this issue to truncate
read-only files. (CVE-2023-4091)
Andrew Bartlett discovered that Samba incorrectly handled the DirSync
control. A remote attacker with an RODC DC account could possibly use this
issue to obtain all domain secrets. (CVE-2023-4154)
Andrew Bartlett discovered that Samba incorrectly handled the rpcecho
development server. A remote attacker could possibly use this issue to
cause Samba to stop responding, resulting in a denial of service.
(CVE-2023-42669)
Kirin van der Veer discovered that Samba incor
Debian
CVE-2023-4091: samba - A vulnerability was discovered in Samba, where the flaw allows SMB clients to tr...
vendor_debian·2023·CVSS 6.5
CVE-2023-4091 [MEDIUM] CVE-2023-4091: samba - A vulnerability was discovered in Samba, where the flaw allows SMB clients to tr...
A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module "acl_xattr" is configured with "acl_xattr:ignore system acls = yes". The SMB protocol allows opening files when the client requests read-only access but then implicitly truncates the opened file to 0 bytes if the client specifies a separate OVERWRITE create disposition request. The issue arises in configurations that bypass kernel file system permissions checks, relying solely on Samba's permissions.
Scope: local
bookworm: resolved (fixed in 2:4.17.12+dfsg-0+deb12u1)
bullseye: resolved (fixed in 2:4.13.13+dfsg-1~deb11u6)
forky: resolved (fixed in 2:4.19.1+dfsg-1)
sid: resolved (fixed in 2:4.19.1+dfsg-1)
trixie: resolved (fixed in 2:4.19.1+d
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://access.redhat.com/errata/RHSA-2023:6209https://access.redhat.com/errata/RHSA-2023:6744https://access.redhat.com/errata/RHSA-2023:7371https://access.redhat.com/errata/RHSA-2023:7408https://access.redhat.com/errata/RHSA-2023:7464https://access.redhat.com/errata/RHSA-2023:7467https://access.redhat.com/security/cve/CVE-2023-4091https://bugzilla.redhat.com/show_bug.cgi?id=2241882https://bugzilla.samba.org/show_bug.cgi?id=15439https://www.samba.org/samba/security/CVE-2023-4091.htmlhttps://access.redhat.com/errata/RHSA-2023:6209https://access.redhat.com/errata/RHSA-2023:6744https://access.redhat.com/errata/RHSA-2023:7371https://access.redhat.com/errata/RHSA-2023:7408https://access.redhat.com/errata/RHSA-2023:7464https://access.redhat.com/errata/RHSA-2023:7467https://access.redhat.com/security/cve/CVE-2023-4091https://bugzilla.redhat.com/show_bug.cgi?id=2241882https://bugzilla.samba.org/show_bug.cgi?id=15439https://lists.debian.org/debian-lts-announce/2024/04/msg00015.htmlhttps://lists.fedoraproject.org/archives/list/[email protected]/message/ZUMVALLFFDFC53JZMUWA6HPD7HUGAP5I/https://security.netapp.com/advisory/ntap-20231124-0002/https://www.samba.org/samba/security/CVE-2023-4091.html
2023-11-03
Published