0.0
NA
CVE-2026-89700
nfsd: validate sockaddr length per family in listener_set
Description

In the Linux kernel, the following vulnerability has been resolved: nfsd: validate sockaddr length per family in listener_set nfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY attribute with no minimum length. A CAP_NET_ADMIN caller can send a 16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte OOB read across three consumers (rpc_cmp_addr_port, svc_find_listener, kernel_bind). nfsd_nl_listener_set_doit() also parsed and validated each listener entry inline in two separate loops, interleaved with mutating the running listener configuration. The validation was duplicated, used an open-coded "nla_len < sizeof(struct sockaddr)" check that was too short for AF_INET6, and handled a malformed entry inconsistently depending on which loop noticed it. Add an nfsd_nl_validate_listeners() helper that walks the entire list once and confirms each entry parses, carries both an address and a transport name, and is long enough for its address family (sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6) for AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking nfsd_mutex or creating the serv, so a malformed request fails cleanly with no side effects. Since every entry is known valid by the time the two existing loops run, drop the redundant presence and per-family length checks from both, leaving only the nla_parse_nested() call needed to extract the data.

INFO

Published Date :

Sept. 11, 2026, 8:19 p.m.

Last Modified :

Sept. 11, 2026, 8:19 p.m.

Remotely Exploit :

No

Source :

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

The following products are affected by CVE-2026-89700 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.

No affected product recoded yet

Solution
Validate sockaddr length and listener entries before processing to prevent out-of-bounds reads.
  • Apply the provided patch to the Linux kernel.
  • Validate listener entries before configuration changes.
  • Ensure sockaddr length checks accommodate all address families.
  • Update related kernel modules to include validation.
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-2026-89700.

URL Resource
https://git.kernel.org/stable/c/22d0e4752ca88fd84196d22ebeedc905e6540440
https://git.kernel.org/stable/c/2aca70c18c5f5d06004122861fb151d5fcc57faf
https://git.kernel.org/stable/c/bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-89700 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-2026-89700 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-2026-89700 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-89700 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. 11, 2026

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: nfsd: validate sockaddr length per family in listener_set nfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY attribute with no minimum length. A CAP_NET_ADMIN caller can send a 16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte OOB read across three consumers (rpc_cmp_addr_port, svc_find_listener, kernel_bind). nfsd_nl_listener_set_doit() also parsed and validated each listener entry inline in two separate loops, interleaved with mutating the running listener configuration. The validation was duplicated, used an open-coded "nla_len < sizeof(struct sockaddr)" check that was too short for AF_INET6, and handled a malformed entry inconsistently depending on which loop noticed it. Add an nfsd_nl_validate_listeners() helper that walks the entire list once and confirms each entry parses, carries both an address and a transport name, and is long enough for its address family (sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6) for AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking nfsd_mutex or creating the serv, so a malformed request fails cleanly with no side effects. Since every entry is known valid by the time the two existing loops run, drop the redundant presence and per-family length checks from both, leaving only the nla_parse_nested() call needed to extract the data.
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89700.json">CVE-2026-89700</a>
    Added Reference https://git.kernel.org/stable/c/22d0e4752ca88fd84196d22ebeedc905e6540440
    Added Reference https://git.kernel.org/stable/c/2aca70c18c5f5d06004122861fb151d5fcc57faf
    Added Reference https://git.kernel.org/stable/c/bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464
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.