CVE-2026-22993
Description
From CVE.org
In the Linux kernel, the following vulnerability has been resolved: idpf: Fix RSS LUT NULL ptr issue after soft reset During soft reset, the RSS LUT is freed and not restored unless the interface is up. If an ethtool command that accesses the rss lut is attempted immediately after reset, it will result in NULL ptr dereference. Also, there is no need to reset the rss lut if the soft reset does not involve queue count change. After soft reset, set the RSS LUT to default values based on the updated queue count only if the reset was a result of a queue count change and the LUT was not configured by the user. In all other cases, don't touch the LUT. Steps to reproduce: ** Bring the interface down (if up) ifconfig eth1 down ** update the queue count (eg., 27->20) ethtool -L eth1 combined 20 ** display the RSS LUT ethtool -x eth1 [82375.558338] BUG: kernel NULL pointer dereference, address: 0000000000000000 [82375.558373] #PF: supervisor read access in kernel mode [82375.558391] #PF: error_code(0x0000) - not-present page [82375.558408] PGD 0 P4D 0 [82375.558421] Oops: Oops: 0000 [#1] SMP NOPTI <snip> [82375.558516] RIP: 0010:idpf_get_rxfh+0x108/0x150 [idpf] [82375.558786] Call Trace: [82375.558793] <TASK> [82375.558804] rss_prepare.isra.0+0x187/0x2a0 [82375.558827] rss_prepare_data+0x3a/0x50 [82375.558845] ethnl_default_doit+0x13d/0x3e0 [82375.558863] genl_family_rcv_msg_doit+0x11f/0x180 [82375.558886] genl_rcv_msg+0x1ad/0x2b0 [82375.558902] ? __pfx_ethnl_default_doit+0x10/0x10 [82375.558920] ? __pfx_genl_rcv_msg+0x10/0x10 [82375.558937] netlink_rcv_skb+0x58/0x100 [82375.558957] genl_rcv+0x2c/0x50 [82375.558971] netlink_unicast+0x289/0x3e0 [82375.558988] netlink_sendmsg+0x215/0x440 [82375.559005] __sys_sendto+0x234/0x240 [82375.559555] __x64_sys_sendto+0x28/0x30 [82375.560068] x64_sys_call+0x1909/0x1da0 [82375.560576] do_syscall_64+0x7a/0xfa0 [82375.561076] ? clear_bhb_loop+0x60/0xb0 [82375.561567] entry_SYSCALL_64_after_hwframe+0x76/0x7e <snip>
Statement
A NULL pointer dereference can be triggered in the idpf driver when an ethtool command accesses the RSS indirection table immediately after a soft reset, as the RSS LUT may have been freed but not reinitialized. This results in a reliable kernel crash and constitutes a local denial-of-service condition, typically requiring CAP_NET_ADMIN privileges.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.7 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | High | Low | N/A |
| Privileges Required | High | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | Low | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart
NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.
Integrity,Confidentiality
Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory
In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.
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