CVE-2023-4091mediumCWE-276

CVE-2023-4091: medium-severity vulnerability in Red Hat Enterprise Linux 6

Samba: smb clients can truncate files with read-only permissions

Published · Updated

Follow this CVE+ Monitor Red Hat Enterprise Linux+ Monitor Red Hat Enterprise Linux 9.2 Extended Update Support

E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.5epss 1.3%
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Affected products
Red Hat · Red Hat Enterprise Linux 6Red Hat · Red Hat Enterprise Linux 7Red Hat · Red Hat Enterprise Linux 8Red Hat · Red Hat Enterprise Linux 8.6 Extended Update SupportRed Hat · Red Hat Enterprise Linux 8.8 Extended Update SupportRed Hat · Red Hat Enterprise Linux 9Red Hat · Red Hat Enterprise Linux 9.0 Extended Update SupportRed Hat · Red Hat Enterprise Linux 9.2 Extended Update SupportRed Hat · Red Hat Storage 3Red Hat · Red Hat Virtualization 4 for Red Hat Enterprise Linux 8
Related CVEs — Red Hat Enterprise Linux 6

In the same product, most dangerous first.

CVE-2023-4911HIGHGlibc: buffer overflow in ld.so leading to privilege escalationEPSS 63.8%KEVCVE-2024-6387HIGHOpenssh: regresshion - race condition in ssh allows rce/dosEPSS 99.5%CVE-2024-3094CRITICALXz: malicious code in distributed sourceEPSS 90.9%CVE-2023-46847HIGHSquid: denial of service in http digest authenticationEPSS 78.5%CVE-2024-12084CRITICALRsync: heap buffer overflow in rsync due to improper checksum length handlingEPSS 72.5%CVE-2023-1183MEDIUMArbitrary file writeEPSS 64.9%