In the Linux kernel, the following vulnerability has been resolved: blk-mq: pop cached request if it is usable When submitting a bio to blk-mq, if the task should sleep after peeking a cached request, but before it pops it, the plug flushes and calls blk_mq_free_plug_rqs, freeing the cached_rqs
Why It Matters
Analysis dossierWhy It Matters
In the Linux kernel, the following vulnerability has been resolved: blk-mq: pop cached request if it is usable When submitting a bio to blk-mq, if the task should sleep after peeking a cached request, but before it pops it, the plug flushes and calls blk_mq_free_plug_rqs, freeing the cached_rqs. This creates a use-after-free bug. Fix this by popping the cached request before any possible blocking calls if it is suitable for use. Popping this request first holds a queue reference, so avoid any serialization races with queue freezes and can safely proceed with dispatching that request to the driver. This potentially increases a timing window from when a driver wants to freeze its queue to when requests stop being dispatched. That scenario is off the fast path though, and drivers need to appropriately handle requests during a freeze request anyway. The downside is the popped element needs to be individually freed when we performed a bio plug merge. The cached request would have had to be freed later anyway, but this patch does it inline with building the plug list instead of after flushing it.
High
Unknown
Unknown
Risk basis: SOC ecosystem technology relevance; HIGH severity; No confirmed exploitation signal in current enrichment
Affected Products & Remediation
1 source-backed product- linux linux kernel · >= 6.1.72 < 6.2; >= 6.1.75 < 6.2; >= 6.5.13 < 6.6; >= 6.6.3 < 6.7; >= 6.6.14 < 6.7; >= 6.7.1 < 6.12.104; >= 6.13 < 6.18.45; >= 6.19 < 7.0.11; 6.7; 7.1 · NVD CPE · Source
Vendor or catalog guidance (source)
Not provided by source
Known exploitation (source facts)
Only what a source states. Unknown means no source has said either way; it is not "not exploited".
- CISA KEV
- Unknown
- Exploited (source statement)
- Unknown
- Publicly disclosed (source)
- Unknown
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
CISA KEV status was not determined for this record.
Change History & Source Data
— No recorded material change
- CNA / source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- Record status · verification
- UPDATED · NVD API
- CPE
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.7:-:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.7:rc2:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.7:rc3:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.7:rc4:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.7:rc5:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.7:rc6:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.7:rc7:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:6.7:rc8:*:*:*:*:*:*, cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*
Evidence & Provenance
— No published hunting query names this record. Browse community and library queries instead.
Correlated briefings
— No published briefing references this CVE