1. Home
  2. Vulnerabilities
  3. CVE-2026-97598
0.0
NA
CVE-2026-97598
ipv4: fib: bound automatic table ID allocation
Overview
Description

In the Linux kernel, the following vulnerability has been resolved: ipv4: fib: bound automatic table ID allocation fib_empty_table() probes every table ID from 1 until it finds a free one. IPv4 tables are stored in a 256-bucket hash table, so a dense set of IDs makes each probe walk a growing hash chain while RTNL is held. Automatic table assignment ("ip rule ... table 0") is an IPv4-only legacy path. Bound the automatically allocated ID to 4096 so the RTNL hold stays bounded, without changing lookups of explicitly specified table IDs. This changes user-visible behavior. A table-0 rule previously received the lowest free ID in 1..RT_TABLE_MAX (0xFFFFFFFF). After this patch the search stops at 4096 and the rule add fails with ENOBUFS if that range is fully occupied. Explicit table IDs above 4096 remain usable. The automatic path is unused in practice: it is IPv4-only, not documented by ip-rule, uncovered by kernel selftests, and both NetworkManager and systemd refuse table 0.

Details
INFO

Published Date :

Sept. 25, 2026, 11:17 a.m.

Last Modified :

Sept. 25, 2026, 11:17 a.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Impact
Affected Products

The following products are affected by CVE-2026-97598 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
Solution
Limit automatic table ID allocation to prevent denial-of-service risks.
  • Apply the kernel patch for fib_empty_table.
  • Update the Linux kernel to the patched version.
  • Verify automatic table ID allocation is bounded.
  • Test rule addition for table 0 after update.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-97598.

URL Resource
https://git.kernel.org/stable/c/2c29c053a6627dc4f12fcfe6b4860bcd9e5d7503
https://git.kernel.org/stable/c/bc8d01d856db106f284b19961af6112e10c3e3b4
https://git.kernel.org/stable/c/efdfb1e27a3328085b79540dfe781d537b576ea1
https://git.kernel.org/stable/c/fe9a906d2bff2d2707bafd6353b5e032a42aeb35
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-97598 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-97598 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-97598 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-97598 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Sep. 25, 2026

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: ipv4: fib: bound automatic table ID allocation fib_empty_table() probes every table ID from 1 until it finds a free one. IPv4 tables are stored in a 256-bucket hash table, so a dense set of IDs makes each probe walk a growing hash chain while RTNL is held. Automatic table assignment ("ip rule ... table 0") is an IPv4-only legacy path. Bound the automatically allocated ID to 4096 so the RTNL hold stays bounded, without changing lookups of explicitly specified table IDs. This changes user-visible behavior. A table-0 rule previously received the lowest free ID in 1..RT_TABLE_MAX (0xFFFFFFFF). After this patch the search stops at 4096 and the rule add fails with ENOBUFS if that range is fully occupied. Explicit table IDs above 4096 remain usable. The automatic path is unused in practice: it is IPv4-only, not documented by ip-rule, uncovered by kernel selftests, and both NetworkManager and systemd refuse table 0.
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/97xxx/CVE-2026-97598.json">CVE-2026-97598</a>
    Added Reference https://git.kernel.org/stable/c/2c29c053a6627dc4f12fcfe6b4860bcd9e5d7503
    Added Reference https://git.kernel.org/stable/c/bc8d01d856db106f284b19961af6112e10c3e3b4
    Added Reference https://git.kernel.org/stable/c/efdfb1e27a3328085b79540dfe781d537b576ea1
    Added Reference https://git.kernel.org/stable/c/fe9a906d2bff2d2707bafd6353b5e032a42aeb35
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
No CVSS metrics available for this vulnerability.