Vulnerability in Linux kernel (CVE-2026-52941)
Summary
Vulnerability in Linux kernel (CVE-2026-52941). 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:
net/smc: avoid NULL deref of conn->lnk in smc_msg_event tracepoint
The smc_msg_event tracepoint class, shared by smc_tx_sendmsg and
smc_rx_recvmsg, unconditionally dereferences smc->conn.lnk:
__string(name, smc->conn.lnk->ibname)
conn->lnk is only set for SMC-R; for SMC-D it is NULL. Other code on
these paths already handles this (e.g. !conn->lnk in
SMC_STAT_RMB_TX_SIZE_SMALL()). With the tracepoint enabled, the first
sendmsg()/recvmsg() on an SMC-D socket crashes:
Oops: general protection fault, probably for non-canonical address
KASAN: null-ptr-deref in range [...]
RIP: 0010:strlen+0x1e/0xa0
Call Trace:
trace_event_raw_event_smc_msg_event (net/smc/smc_tracepoint.h:44)
smc_rx_recvmsg (net/smc/smc_rx.c:515)
smc_recvmsg (net/smc/af_smc.c:2859)
__sys_recvfrom (net/socket.c:2315)
__x64_sys_recvfrom (net/socket.c:2326)
do_syscall_64
The faulting address 0x3e0 is offsetof(struct smc_link, ibname),
confirming the NULL ->lnk deref. Enabling the tracepoint requires
root, but the trigger itself is unprivileged: socket(AF_SMC, ...) has
no capability check, and SMC-D negotiation needs no admin step on
s390 or on x86 with the loopback ISM device loaded.
Log an empty device name for SMC-D instead of dereferencing NULL.
Source: GitHub Security Advisories (Global) 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-2026-52941 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure. CVSS score: 5.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-52941" on the vendor's site.
CVE-2026-52941 (Linux kernel) — CWE-476 / CVSS v3 5.5
Attack vector: local / no user interaction
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 (CWE-476) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: Medium (CVSS 5.5/10). 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
- Debian DEBIAN-CVE-2026-52941 linux Fixed in: 6.1.176-1
- Ubuntu UBUNTU-CVE-2026-52941 linux-hwe-edge
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 git.kernel.org
- web git.kernel.org
- web github.com