Vulnerability in Linux kernel (CVE-2026-93231)
Summary
Vulnerability in Linux kernel (CVE-2026-93231). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
lockd: fix swapped arguments in nlmsvc_match_ip()
When releasing locks by server IP address via /proc/fs/nfsd/unlock_ip,
nlmsvc_unlock_all_by_ip() calls nlm_traverse_files() with the server
sockaddr as the opaque @data argument:
nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);
The match callback is later invoked from nlm_traverse_locks() as:
match(lockhost, host);
where the first argument is the nlm_host that owns the lock, and the
second argument is the @data that was originally passed down (here the
server sockaddr). This is the convention every other match callback
relies on (nlmsvc_mark_host(), nlmsvc_same_host(), nlmsvc_is_client()):
arg1 is the real nlm_host, arg2 is the caller-supplied reference value.
nlmsvc_match_ip() has had these two arguments reversed ever since the
unlock-by-IP feature was introduced in commit 4373ea84c84d ("lockd:
unlock lockd locks associated with a given server ip"):
return rpc_cmp_addr(nlm_srcaddr(host), datap);
Here @host is actually the server sockaddr, so nlm_srcaddr(host)
dereferences a struct sockaddr as a struct nlm_host and reads garbage
at the offset of h_srcaddr; meanwhile @datap is actually the lock
owner's nlm_host but is compared as a sockaddr. As a result the
comparison practically never matches and locks are not released for the
requested IP.
Swap the arguments so the lock owner's source address is compared
against the requested server addr…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-93231 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-93231" on the vendor's site.
CVE-2026-93231 (Linux kernel)
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Ubuntu UBUNTU-CVE-2026-93231 linux
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com