CVE-2026-98821
Microsoft — block: reject polled dio with user integrity metadata
Microsoft · Not classified by connected sources
EVRS 0 of 100 Informational
Monitor
Rank 2,937 of 2,960 tracked
Why it scores 0
Evidence available: 2 of 8 signalsNo strong exploitation, disclosure, or severity signal is available for this CVE yet.
- CISA KEVDid not apply
- RansomwareNo data
- Vendor exploitationNo data
- EPSSDid not apply
- Microsoft Exploitability IndexNo data
- Pre-patch disclosureNo data
- KEV recencyNo data
- CVSSNo data
The band answers “how soon”, not “how bad”. No data for: Ransomware, Vendor exploitation, Microsoft Exploitability Index, Pre-patch disclosure, KEV recency, CVSS. Why some signals show no data
Fix
No fixed version identified yetAffected versions
Not identified by the connected sources
Remediation
NVD lists one or more references for this CVE that aren't tagged as a patch or vendor advisory. Review them directly to confirm patch availability and applicability before making a remediation decision.
Evidence
Each value with its source| Measure | Value | Source |
|---|---|---|
| CVSS base scoreHow severe the flaw is in itself. It does not say how likely an attack is. | Not publishedNVD and the CVE record were checked and hold no score. | NVD |
| FIRST EPSSFIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. | 0.002 (5.5th pctl) | FIRST EPSS |
| Actively exploitedWhether a source of record has confirmed attacks using it in the wild. | Not confirmed | Patch Tuesday |
| Public exploit moduleA module existing is not the same as active exploitation. | None known | Metasploit |
| EUVD cross-referenceENISA's record: CVSS 0.0, assigned by Linux. | Listed | ENISA EUVD |
Description
NVDIn the Linux kernel, the following vulnerability has been resolved: block: reject polled dio with user integrity metadata IOCB_HAS_METADATA leaves iocb->private as a uio_meta, while iocb_bio_iopoll() expects a bio. Since 2729a60bbfb9, metadata I/O always uses __blkdev_direct_IO(), which never publishes the bio for polling, so IOPOLL calls bio_poll() on the uio_meta. Reproducer: io_uring IOPOLL plus a PI attribute on an integrity device (scsi_debug dif=1 dix=1). KASAN reports: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000004 KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] RIP: 0010:bio_poll+0x9d/0x4b0 Call Trace: iocb_bio_iopoll+0x5b/0x80 io_uring_classic_poll+0xf3/0x140 io_do_iopoll+0x4e3/0xc00 io_iopoll_check+0x275/0x560 __do_sys_io_uring_enter+0x2e5/0x720 Return -EOPNOTSUPP when HIPRI is combined with user metadata.