CVE-2025-21640
mediumpriority · track · 22EPSS 0.002 · 15 %ileDEEURUUSEPSS · scored 2026-10-27
In the Linux kernel, the following vulnerability has been resolved: sctp: sysctl: cookie_hmac_alg: avoid using current->nsproxy As mentioned in a previous commit of this series, using the 'net' structure via 'current' is not recommended for different reasons: - Inconsistency: getting info from the reader's/writer's netns vs only from the opener's netns. - current->nsproxy can be NULL in some cases, resulting in an 'Oops' (null-ptr-deref), e.g. when the current task is exiting, as spotted by syzbot [1] using acct(2). The 'net' structure can be obtained from the table->data using container_of(). Note that table->data could also be used directly, as this is the only member needed from the 'net' structure, but that would increase the size of this fix, to use '*data' everywhere 'net->sctp.sctp_hmac_alg' is used.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
No vendor fix yet; a mitigation is available.
- MitigationSIMATIC S7-1500 TM MFP - GNU/Linux subsystemsiemens_psirt
Limit access to the interactive shell of the additional GNU/Linux subssytem to trusted personnel only.
- MitigationSIMATIC S7-1500 TM MFP - GNU/Linux subsystemcisa_csaf_ot
Limit access to the interactive shell of the additional GNU/Linux subssytem to trusted personnel only.
- No fix availableSIMATIC S7-1500 TM MFP - GNU/Linux subsystemsiemens_psirt
Currently no fix is available
- No fix availableSIMATIC S7-1500 TM MFP - GNU/Linux subsystemcisa_csaf_ot
Currently no fix is available
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 · 5.1–7.1
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (70)
Products and version ranges known to be affected.
advisories (4)
Vendor and ecosystem advisories describing this.
- SSA-265688SSA-265688: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.12024-04-09csaf · siemens_psirtDE
Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.1. Siemens has released a new version for SIMATIC S7-1500 TM MFP - GNU/Linux subsystem and recommends to update to the latest version. Siemens is preparing further fixes and recommends specific mitigations for products where fixes are not or not yet available. SIMATIC S7-1500 TM MFP V1.1 is no longer maintained and there won't be any update to the CVE list anymore. Please update to the latest version. Note: This SSA advises vulnerabilities for firmware version V1.1 only; for version V1.1.1 refer to SSA-784472.
- WID-SEC-W-2025-0119Linux Kernel: Mehrere SchwachstellenDeutsch2025-01-19csaf · cert_bundDE
Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen oder andere nicht spezifizierte Auswirkungen zu verursachen.
- WID-SEC-W-2025-1439Dell Secure Connect Gateway: Mehrere Schwachstellen ermöglichen nicht spezifizierten AngriffDeutsch2025-06-30csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell Secure Connect Gateway ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.
- ICSA-24-102-01Siemens SIMATIC S7-1500 TM MFP2024-04-09icsa · cisa_csaf_otUS
Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.1. Siemens is preparing fix versions and recommends specific countermeasures for products where fixes are not, or not yet available.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (23)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2025-21640cnnvd
- https://git.kernel.org/stable/c/3cd0659deb9c03535fd61839e91d4d4d3e51ac71cnnvd
- https://git.kernel.org/stable/c/ad673e514b2793b8d5902f6ba6ab7e890dea23d5cnnvd
- https://git.kernel.org/stable/c/ea62dd1383913b5999f3d16ae99d411f41b528d4cnnvd
- https://git.kernel.org/stable/c/f0bb3935470684306e4e04793a20ac4c4b08de0bcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2025-21640cnnvd
- https://git.kernel.org/stable/c/03ca51faba2b017bf6c90e139434c4117d0afcdcenisa_euvd
- https://git.kernel.org/stable/c/3cd0659deb9c03535fd61839e91d4d4d3e51ac71enisa_euvd
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