CVE-2025-39857
mediumpriority · track · 22EPSS 0.003 · 24 %ileDEEUNLRUUSEPSS · scored 2026-10-27
In the Linux kernel, the following vulnerability has been resolved: net/smc: fix one NULL pointer dereference in smc_ib_is_sg_need_sync() BUG: kernel NULL pointer dereference, address: 00000000000002ec PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP PTI CPU: 28 UID: 0 PID: 343 Comm: kworker/28:1 Kdump: loaded Tainted: G OE 6.17.0-rc2+ #9 NONE Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 Workqueue: smc_hs_wq smc_listen_work [smc] RIP: 0010:smc_ib_is_sg_need_sync+0x9e/0xd0 [smc] ... Call Trace: <TASK> smcr_buf_map_link+0x211/0x2a0 [smc] __smc_buf_create+0x522/0x970 [smc] smc_buf_create+0x3a/0x110 [smc] smc_find_rdma_v2_device_serv+0x18f/0x240 [smc] ? smc_vlan_by_tcpsk+0x7e/0xe0 [smc] smc_listen_find_device+0x1dd/0x2b0 [smc] smc_listen_work+0x30f/0x580 [smc] process_one_work+0x18c/0x340 worker_thread+0x242/0x360 kthread+0xe7/0x220 ret_from_fork+0x13a/0x160 ret_from_fork_asm+0x1a/0x30 </TASK> If the software RoCE device is used, ibdev->dma_device is a null pointer. As a result, the problem occurs. Null pointer detection is added to prevent problems.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedSIMATIC CN 4100siemens_psirt
Update to V5.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814144/ - FixedSIMATIC CN 4100cisa_csaf_ot
Update to V5.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814144/
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.8–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (96)
Products and version ranges known to be affected.
advisories (4)
Vendor and ecosystem advisories describing this.
- NCSC-2026-0147Kwetsbaarheden verholpen in Siemens-productenNL2026-05-13csaf · ncsc_nlNL
Siemens heeft kwetsbaarheden verholpen in verschillende (OT-)producten. Het gaat onder andere om producten in de Siemens RUGGEDCOM-, SCALANCE-, SIMATIC-, SIMIT-, SINAMICS-, SIPROTEC-, SENTRON- en Solid Edge-productreeksen.
- SSA-032379SSA-032379: Multiple Vulnerabilities in SIMATIC CN 4100 Before V5.02026-05-12csaf · siemens_psirtDE
SIMATIC CN 4100 contains multiple vulnerabilities which could potentially lead to a compromise in availability, integrity and confidentiality. Siemens has released a new version for SIMATIC CN 4100 and recommends to update to the latest version.
- WID-SEC-W-2025-2099Linux Kernel: Mehrere SchwachstellenDeutsch2025-09-21csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen oder nicht näher beschriebene Auswirkungen zu erzielen.
- ICSA-26-134-10Siemens SIMATIC2026-05-12icsa · cisa_csaf_otUS
SIMATIC CN 4100 contains multiple vulnerabilities which could potentially lead to a compromise in availability, integrity and confidentiality. Siemens has released a new version for SIMATIC CN 4100 and recommends to update to the latest version.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (19)
External citations — patches, advisories, analysis.
- https://git.kernel.org/stable/c/0cdf1fd8fc59d44a48c694324611136910301ef9cnnvd
- https://git.kernel.org/stable/c/34f17cbe027050b8d5316ea1b6f9bd7c378e92decnnvd
- https://git.kernel.org/stable/c/ba1e9421cf1a8369d25c3832439702a015d6b5f9cnnvd
- https://git.kernel.org/stable/c/eb929910bd4b4165920fa06a87b22cc6cae92e0ecnnvd
- https://git.kernel.org/stable/c/f18d9b3abf9c6587372cc702f963a7592277ed56cnnvd
- https://vigilance.fr/vulnerability/Linux-kernel-multiple-vulnerabilities-dated-22-09-2025-48265cnnvd
- https://www.kernel.org/Patchcnnvd
- https://git.kernel.org/stable/c/0cdf1fd8fc59d44a48c694324611136910301ef9enisa_euvd
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