CVE-2023-39189

Kernel: netfilter: nftables out-of-bounds read in nf_osf_match_one()

Description

A flaw was found in the Netfilter subsystem in the Linux kernel. The nfnl_osf_add_callback function did not validate the user mode controlled opt_num field. This flaw allows a local privileged (CAP_NET_ADMIN) attacker to trigger an out-of-bounds read, leading to a crash or information disclosure.

Remediation

Workaround:

  • This flaw can be mitigated by preventing the affected Passive OS Fingerprinting match module (`xt_osf`) from being loaded. For instructions on how to blacklist a kernel module, please see https://access.redhat.com/solutions/41278.

Category

5.1
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.01%
Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com
Affected: Red Hat Red Hat Enterprise Linux 8
Affected: Red Hat Red Hat Enterprise Linux 8
Affected: Red Hat Red Hat Enterprise Linux 9
Affected: Red Hat Red Hat Enterprise Linux 9
Affected: Red Hat Red Hat Enterprise Linux 6
Affected: Red Hat Red Hat Enterprise Linux 7
Affected: Red Hat Red Hat Enterprise Linux 7
Affected: Red Hat Red Hat Enterprise Linux 9
Published at:
Updated at:

References

Link Tags
https://access.redhat.com/errata/RHSA-2024:2394 vendor advisory
https://access.redhat.com/errata/RHSA-2024:2950 vendor advisory
https://access.redhat.com/errata/RHSA-2024:3138 vendor advisory
https://access.redhat.com/security/cve/CVE-2023-39189 third party advisory vdb entry
https://bugzilla.redhat.com/show_bug.cgi?id=2226777 third party advisory issue tracking patch
https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html

Frequently Asked Questions

What is the severity of CVE-2023-39189?
CVE-2023-39189 has been scored as a medium severity vulnerability.
How to fix CVE-2023-39189?
As a workaround for remediating CVE-2023-39189: This flaw can be mitigated by preventing the affected Passive OS Fingerprinting match module (`xt_osf`) from being loaded. For instructions on how to blacklist a kernel module, please see https://access.redhat.com/solutions/41278.
Is CVE-2023-39189 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-39189 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-39189?
CVE-2023-39189 affects Red Hat Red Hat Enterprise Linux 8, Red Hat Red Hat Enterprise Linux 8, Red Hat Red Hat Enterprise Linux 9, Red Hat Red Hat Enterprise Linux 9, Red Hat Red Hat Enterprise Linux 6, Red Hat Red Hat Enterprise Linux 7, Red Hat Red Hat Enterprise Linux 7, Red Hat Red Hat Enterprise Linux 9.
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