CVE-2023-42755: Kernel: rsvp: out-of-bounds read in rsvp_classify()

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-10-05 · updated 2026-10-15
Weakness: CWE-125

Description

A flaw was found in the IPv4 Resource Reservation Protocol (RSVP) classifier in the Linux kernel. The xprt pointer may go beyond the linear part of the skb, leading to an out-of-bounds read in the `rsvp_classify` function. This issue may allow a local user to crash the system and cause a denial of service.

Affected products

Debian Linux: 10.0
Linux kernel: before 6.3 — fixed in 6.3
Red Hat Enterprise Linux: 8.0

How to fix

Upgrade to a fixed version: Linux kernel 6.3. Check the vendor advisory for mitigations.

References

https://access.redhat.com/errata/RHSA-2024:2950
https://access.redhat.com/errata/RHSA-2024:3138
https://access.redhat.com/security/cve/CVE-2023-42755
https://bugzilla.redhat.com/show_bug.cgi?id=2239847
https://seclists.org/oss-sec/2023/q3/229
https://access.redhat.com/errata/RHSA-2024:2950
https://access.redhat.com/errata/RHSA-2024:3138
https://access.redhat.com/security/cve/CVE-2023-42755
https://bugzilla.redhat.com/show_bug.cgi?id=2239847
https://lists.debian.org/debian-lts-announce/2023/10/msg00027.html
https://lists.debian.org/debian-lts-announce/2024/01/msg00004.html
https://seclists.org/oss-sec/2023/q3/229

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