In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg Issuing two writes to the same af_alg socket is bogus as the data will be interleaved in an unpredictable fashion
Why It Matters
Analysis dossierWhy It Matters
In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg Issuing two writes to the same af_alg socket is bogus as the data will be interleaved in an unpredictable fashion. Furthermore, concurrent writes may create inconsistencies in the internal socket state. Disallow this by adding a new ctx->write field that indiciates exclusive ownership for writing.
Immediate Attention
Yes
Unknown
Risk basis: CISA KEV exploitation signal; SOC ecosystem technology relevance; HIGH severity; Known exploitation signal from CISA KEV or ransomware metadata
Affected Products & Remediation
3 source-backed products- linux linux kernel · >= 2.6.38 < 5.10.245; >= 5.11 < 5.15.194; >= 5.16 < 6.1.154; >= 6.2 < 6.6.108; >= 6.7 < 6.12.49; >= 6.13 < 6.16.9; 6.17 · NVD CPE · Source
- siemens simatic s7-1500 cpu 1518-4 pn\/dp mfp firmware · >= 3.1.6 · NVD CPE · Source
- siemens simatic s7-1500 cpu 1518f-4 pn\/dp mfp firmware · >= 3.1.6 · NVD CPE · Source
Vendor or catalog guidance (source)
- CISA KEV: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Known exploitation (source facts)
Only what a source states. Unknown means no source has said either way; it is not "not exploited".
- CISA KEV
- Listed
- Exploited (source statement)
- Yes
- Publicly disclosed (source)
- Unknown
CISA required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Suggested hunting (rule-based inference)
SecOps Signal recommendation (rule-based inference). These steps are hunting hypotheses from the vulnerability class; they do not state or imply that exploitation occurred here or anywhere.
Matched local-privilege-escalation (CVSS AV:L, CVSS PR:L)
Exposure
- Identify hosts reporting this CVE, prioritising shared or multi-user systems.Telemetry: DeviceTvmSoftwareVulnerabilities · A local, low-privilege vector matters most where untrusted users can run code. · Rule local-privilege-escalation
Exploitation evidence
- Look for low-privileged processes spawning SYSTEM or root-level child processes on affected hosts.Telemetry: DeviceProcessEvents · Hunting hypothesis from the CVSS vector; privilege transitions are a focused starting point, not evidence of attack. · Rule local-privilege-escalation
Response
- Confirm the source-stated update on affected hosts.Telemetry: DeviceTvmSoftwareVulnerabilities · Host inventory can verify remediation. · Rule local-privilege-escalation
CISA KEV Record
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Change History & Source Data
— No recorded material change
- CNA / source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- Record status · verification
- UPDATED · CISA KEV confirmed
- CPE
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.17:rc6:*:*:*:*:*:*, cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518-4_pn\/dp_mfp_firmware:*:*:*:*:*:*:*:*, cpe:2.3:h:siemens:simatic_s7-1500_cpu_1518-4_pn\/dp_mfp:*:*:*:*:*:*:*:*, cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518f-4_pn\/dp_mfp_firmware:*:*:*:*:*:*:*:*
Evidence & Provenance
Linked by the query's stored exact CVE association. Review required tables and validation status before use.
DeviceTvmSoftwareVulnerabilities| where CveId == "CVE-2025-39964"| project DeviceId, DeviceName, OSPlatform, OSVersion, SoftwareVendor, SoftwareName, SoftwareVersion, CveId, VulnerabilitySeverityLevel, RecommendedSecurityUpdate, RecommendedSecurityUpdateId| sort by VulnerabilitySeverityLevel descCorrelated briefings
— No published briefing references this CVE