CVE-2025-39673
mediumpriority · track · 19EPSS 0.003 · 23 %ileDEEUNLRUUSEPSS · scored 2026-10-27
In the Linux kernel, the following vulnerability has been resolved: ppp: fix race conditions in ppp_fill_forward_path ppp_fill_forward_path() has two race conditions: 1. The ppp->channels list can change between list_empty() and list_first_entry(), as ppp_lock() is not held. If the only channel is deleted in ppp_disconnect_channel(), list_first_entry() may access an empty head or a freed entry, and trigger a panic. 2. pch->chan can be NULL. When ppp_unregister_channel() is called, pch->chan is set to NULL before pch is removed from ppp->channels. Fix these by using a lockless RCU approach: - Use list_first_or_null_rcu() to safely test and access the first list entry. - Convert list modifications on ppp->channels to their RCU variants and add synchronize_net() after removal. - Check for a NULL pch->chan before dereferencing it.
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–critical · 4.3–9.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (104)
Products and version ranges known to be affected.
- NetApp ActiveIQ Unified Manager VMware vSphereall versionscert_bundDEcpe:/a:netapp:active_iq_unified_manager:vmware_vsphere
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-2025-1988Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2025-09-07csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen oder nicht näher spezifizierte 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 (21)
External citations — patches, advisories, analysis.
- https://git.kernel.org/stable/c/0417adf367a0af11adf7ace849af4638cfb573f7cnnvd
- https://git.kernel.org/stable/c/0f1630be6fcca3f0c63e4b242ad202e5cde28a40cnnvd
- https://git.kernel.org/stable/c/94731cc551e29511d85aa8dec61a6c071b1f2430cnnvd
- https://git.kernel.org/stable/c/9a1969fbffc1f1900d92d7594b1b7d8d72ef3dc7cnnvd
- https://git.kernel.org/stable/c/ca18d751bcc9faf5b7e82e9fae1223d103928181cnnvd
- https://git.kernel.org/stable/c/f97f6475fdcb3c28ff3c55cc4b7bde632119ec08cnnvd
- https://www.kernel.org/Patchcnnvd
- https://git.kernel.org/stable/c/0417adf367a0af11adf7ace849af4638cfb573f7enisa_euvd
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