CVE-2026-64103 — scsi: isci: Fix use-after-free in device removal path
In the Linux kernel, the following vulnerability has been resolved: scsi: isci: Fix use-after-free in device removal path The ISCI completion tasklet is initialized in isci_host_alloc() (drivers/scsi/isci/init.c:496) and scheduled from both MSI-X and legacy interrupt handlers (drivers/scsi/isci/host.c:223,613). isci_host_deinit() stops the controller and waits for stop completion, but it never kills completion_tasklet before teardown continues. A top-of-function tasklet_kill() is not sufficient here: interrupts are only disabled when isci_host_stop_complete() runs, so until wait_for_stop() returns the IRQ handlers can still requeue the tasklet. The tasklet callback also re-enables interrupts after draining completions, so killing the tasklet before the source is quiesced leaves the same race open. Once wait_for_stop() returns, no further IRQ-driven scheduling can occur. Kill completion_tasklet there so teardown cannot race a queued tasklet running on a dead ihost. On remove or unload, the stale callback can otherwise dereference ihost and touch ihost->smu_registers after the host lifetime ends. A UML + KASAN analogue reproduced the failure class both with no tasklet_kill() and with tasklet_kill() placed before source quiesce, and stayed clean once the kill happened after quiescing the scheduling source. This mirrors commit f6ab594672d4 ("scsi: aic94xx: fix use-after-free in device removal path"), but ISCI needs the kill after wait_for_stop().
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
version 3.0≥ 6f231dda68080759f1aed3769896e94c73099f0f and < b52a8d52c3125ec9a93106ed816582368de34426≥ 6f231dda68080759f1aed3769896e94c73099f0f and < 6d40f2f103bb30f52f3dbadbe2c3fdf274a9763c≥ 6f231dda68080759f1aed3769896e94c73099f0f and < b9ff8631006233ba246828ac70409d2cb2da38d3≥ 6f231dda68080759f1aed3769896e94c73099f0f and < cb9e72c50e6c81a5903f27e0b397ce8525d7539b≥ 6f231dda68080759f1aed3769896e94c73099f0f and < 309c6058622d080fe8c2fab87c30da82d834d989≥ 6f231dda68080759f1aed3769896e94c73099f0f and < ab2266601a875982f2d2033f41e070a6d5e615e2≥ 6f231dda68080759f1aed3769896e94c73099f0f and < a83d3e4daba40d49324cec1c51ed261e1ea48cf1 and 1 more≥ 6f231dda68080759f1aed3769896e94c73099f0f and < 1412995e10c74644b47f242aea6e4f3d4180e806 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
version 7.1-rc2version 7.1-rc4version 7.1-rc3≥ 3.0.1 and < 5.10.258version 7.1-rc1version 3.0-rc7version 3.0-rc6version 3.0 and 6 more≥ 6.19 and < 7.0.11≥ 6.13 and < 6.18.34≥ 6.7 and < 6.12.92≥ 6.2 and < 6.6.142≥ 5.16 and < 6.1.175≥ 5.11 and < 5.15.209 |
Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 7.8
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
8 on the record
- git.kernel.org/stable/c/b9ff8631006233ba246828ac70409d2cb2da38d3
- git.kernel.org/stable/c/ab2266601a875982f2d2033f41e070a6d5e615e2
- git.kernel.org/stable/c/cb9e72c50e6c81a5903f27e0b397ce8525d7539b
- git.kernel.org/stable/c/b52a8d52c3125ec9a93106ed816582368de34426
- git.kernel.org/stable/c/309c6058622d080fe8c2fab87c30da82d834d989
- git.kernel.org/stable/c/a83d3e4daba40d49324cec1c51ed261e1ea48cf1
- git.kernel.org/stable/c/1412995e10c74644b47f242aea6e4f3d4180e806
- git.kernel.org/stable/c/6d40f2f103bb30f52f3dbadbe2c3fdf274a9763c
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 9h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 9h
- Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 1d
- Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 1d
- Unknown CVE-2026-98429 RDMA/efa: Keep EQ resources alive while IRQ is registered 1d
- Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No FIRST EPSS score.
- No CISA SSVC assessment.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-64103 is "scsi: isci: Fix use-after-free in device removal path", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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