Unknown

CVE-2026-89784 — SUNRPC: check rpc_sockaddr2uaddr() return value in rpcb_register_inet4/6

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: check rpc_sockaddr2uaddr() return value in rpcb_register_inet4/6 rpcb_register_inet4() and rpcb_register_inet6() store the result of rpc_sockaddr2uaddr() into map->r_addr without checking it for NULL. rpc_sockaddr2uaddr() returns NULL when its final kstrdup() fails, and the unchecked NULL is then carried into the synchronous RPCBPROC_SET encode path: rpcb_register_call() -> rpc_call_sync() -> rpcb_enc_getaddr() -> encode_rpcb_string(), whose first statement is strlen(string), dereferencing NULL and oopsing the kernel. The crash reproduces under failslab on v6.12; with KASAN the NULL dereference surfaces as a fault on the shadow of address zero: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000 [#1] PREEMPT SMP KASAN RIP: 0010:strlen (lib/string.c:409) Call Trace: encode_rpcb_string (net/sunrpc/rpcb_clnt.c:890) rpcb_enc_getaddr (net/sunrpc/rpcb_clnt.c:910) rpcauth_wrap_req_encode (net/sunrpc/auth.c:745) call_encode (net/sunrpc/clnt.c:1966) __rpc_execute (net/sunrpc/sched.c:952) rpc_run_task (net/sunrpc/clnt.c:1243) rpc_call_sync (net/sunrpc/clnt.c:1272) rpcb_v4_register (net/sunrpc/rpcb_clnt.c:500) svc_generic_rpcbind_set nfsd_rpcbind_set svc_register svc_setup_socket svc_addsock write_ports nfsctl_transaction_write vfs_write The crash is reachable when an in-kernel RPC service (nfsd, lockd, nfs-callback) registers with the local rpcbind under enough memory pressure for the small GFP_KERNEL kstrdup() in rpc_sockaddr2uaddr() to fail. The asynchronous getport path already handles this exact failure mode by returning -ENOMEM; only the two register helpers omit the check. Mirror that handling: bail out with -ENOMEM when rpc_sockaddr2uaddr() returns NULL, before the address is fed into the encoder.

Published Sep 16, 2026 · Updated Oct 19, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+2

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.21%

ahead of 11% of scored CVEs · Oct 20, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ d77385f23830ee6c400569bac8b37e6eb3b7d360 and < 04441b792ec40eb66349b5fab34b6a2090b5b2dd≥ d77385f23830ee6c400569bac8b37e6eb3b7d360 and < 5a51c49ddb37b883566874aecc66bc5a2e617a96≥ d77385f23830ee6c400569bac8b37e6eb3b7d360 and < 4a6095de8cb1858e05bdf70b3e7d6d7645c25041≥ d77385f23830ee6c400569bac8b37e6eb3b7d360 and < 12bf3e0182ccdaf3b412756a756d3944a7dacaa9≥ d77385f23830ee6c400569bac8b37e6eb3b7d360 and < 4e01022974355732e748ec8ebc97c558cb624ffe≥ d77385f23830ee6c400569bac8b37e6eb3b7d360 and < cda4aacfb0bbf5c0f90fd0b42c72c749635d1368≥ d77385f23830ee6c400569bac8b37e6eb3b7d360 and < eb476289c12cc22c8766f8a84eeb7ab46c4e8fb6≥ d77385f23830ee6c400569bac8b37e6eb3b7d360 and < fd22370226a0d8109045d0831fd5aaadee921693 and 1 more version 3.2	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 20, 2026 · 5 reading(s) · max 0.21%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 16, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× References added · Oct 19, 2026 – Oct 19, 2026
1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

10 on the record

git.kernel.org/stable/c/4a6095de8cb1858e05bdf70b3e7d6d7645c25041
NIST National Vulnerability Database
git.kernel.org/stable/c/12bf3e0182ccdaf3b412756a756d3944a7dacaa9
NIST National Vulnerability Database
git.kernel.org/stable/c/eb476289c12cc22c8766f8a84eeb7ab46c4e8fb6
NIST National Vulnerability Database
git.kernel.org/stable/c/fd22370226a0d8109045d0831fd5aaadee921693
NIST National Vulnerability Database
git.kernel.org/stable/c/4e01022974355732e748ec8ebc97c558cb624ffe
NIST National Vulnerability Database
nvd.nist.gov/vuln/detail/CVE-2026-89784
GitHub Security Advisories
git.kernel.org/stable/c/04441b792ec40eb66349b5fab34b6a2090b5b2dd
NIST National Vulnerability Database
git.kernel.org/stable/c/5a51c49ddb37b883566874aecc66bc5a2e617a96
NIST National Vulnerability Database
github.com/advisories/GHSA-8jpc-3w39-9jvg
GitHub Security Advisories
git.kernel.org/stable/c/cda4aacfb0bbf5c0f90fd0b42c72c749635d1368
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-98869 bpf: Infer zext_dst based on static register liveness analysis 9h
Unknown CVE-2023-7356 Bluetooth: ISO: Copy BASE if service data matches EIR_BAA_SERVICE_UUID 9h
Unknown CVE-2026-98866 sched/cache: Introduce task_struct->sched_cache_grp to fix UAF 3d
Unknown CVE-2026-98867 dm-pcache: bound the logical key offset from persistent memory 3d
Unknown CVE-2026-98868 dm-pcache: reject a kset that overruns its segment 3d
Unknown CVE-2026-98856 kprobes: Skip disarmed probes when checking optkprobe overlap 3d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-89784 is "SUNRPC: check rpc_sockaddr2uaddr() return value in rpcb_register_inet4/6", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.21% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.