In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Reserve extra IRQ vectors
Commit a6dcfe08487e ("scsi: qla2xxx: Limit interrupt vectors to number of
CPUs") lowers the number of allocated MSI-X vectors to the number of CPUs.
That breaks vector allocation assumptions in qla83xx_iospace_config(),
qla24xx_enable_msix() and qla2x00_iospace_config(). Either of the functions
computes maximum number of qpairs as:
ha->max_qpairs = ha->msix_count - 1 (MB interrupt) - 1 (default
response queue) - 1 (ATIO, in dual or pure target mode)
max_qpairs is set to zero in case of two CPUs and initiator mode. The
number is then used to allocate ha->queue_pair_map inside
qla2x00_alloc_queues(). No allocation happens and ha->queue_pair_map is
left NULL but the driver thinks there are queue pairs available.
qla2xxx_queuecommand() tries to find a qpair in the map and crashes:
if (ha->mqenable) {
uint32_t tag;
uint16_t hwq;
struct qla_qpair *qpair = NULL;
tag = blk_mq_unique_tag(cmd->request);
hwq = blk_mq_unique_tag_to_hwq(tag);
qpair = ha->queue_pair_map[hwq]; # <- HERE
if (qpair)
return qla2xxx_mqueuecommand(host, cmd, qpair);
}
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 0 PID: 72 Comm: kworker/u4:3 Tainted: G W 5.10.0-rc1+ #25
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Workqueue: scsi_wq_7 fc_scsi_scan_rport [scsi_transport_fc]
RIP: 0010:qla2xxx_queuecommand+0x16b/0x3f0 [qla2xxx]
Call Trace:
scsi_queue_rq+0x58c/0xa60
blk_mq_dispatch_rq_list+0x2b7/0x6f0
? __sbitmap_get_word+0x2a/0x80
__blk_mq_sched_dispatch_requests+0xb8/0x170
blk_mq_sched_dispatch_requests+0x2b/0x50
__blk_mq_run_hw_queue+0x49/0xb0
__blk_mq_delay_run_hw_queue+0xfb/0x150
blk_mq_sched_insert_request+0xbe/0x110
blk_execute_rq+0x45/0x70
__scsi_execute+0x10e/0x250
scsi_probe_and_add_lun+0x228/0xda0
__scsi_scan_target+0xf4/0x620
? __pm_runtime_resume+0x4f/0x70
scsi_scan_target+0x100/0x110
fc_scsi_scan_rport+0xa1/0xb0 [scsi_transport_fc]
process_one_work+0x1ea/0x3b0
worker_thread+0x28/0x3b0
? process_one_work+0x3b0/0x3b0
kthread+0x112/0x130
? kthread_park+0x80/0x80
ret_from_fork+0x22/0x30
The driver should allocate enough vectors to provide every CPU it's own HW
queue and still handle reserved (MB, RSP, ATIO) interrupts.
The change fixes the crash on dual core VM and prevents unbalanced QP
allocation where nr_hw_queues is two less than the number of CPUs.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-25). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is referenced, but no release containing it is confirmed. Check the referenced fix and the vendor's advisory for a release that contains it; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation on your normal schedule.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says. In the directive's words, “Fix on system upgrade” means that, “unless conditions change”, the vulnerability “should be remediated the next time the vulnerable asset receives a scheduled major upgrade or rebuild”: its timelines are “dynamic as facts change”, and a KEV listing shortens them.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it