CVE-2026-81009

UNRATEDCVSS · not yet scoredTrending — 3 sources updated this week
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EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • No CVSS published and no exploitation signals yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS v2: —Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

io_uring/query: cap user size passed to copy_struct_to_user

io_handle_query_entry() clamps hdr.size for the inbound copy_from_user() but keeps the original user value as usize. copy_struct_to_user() uses that usize and, when it is larger than the kernel result, clear_user()s the trailing bytes.

As hdr.size is a __u32, a query can request nearly 4 GiB of zeroing, including on the error path where res_size stays 0. The interface is reachable without a ring via IORING_REGISTER_QUERY.

Reject sizes larger than PAGE_SIZE, as recommended for copy_struct_* interfaces.

CVSS v3
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EchelonGraph score
Not yet assessedNo source has published severity data for this CVE yet — no CVSS score from NVD or a CNA, no GitHub advisory, and it is not in CISA KEV. This is not a rating of zero; we cannot assess it yet.
EG Score
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EG Risk
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EPSS PROB
0.2%
EPSS %ILE
5th
KEV
Not listed

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” 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

Published

September 11, 2026

Last Modified

September 11, 2026

Vendor Advisories for CVE-2026-81009(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 7.2~rc7-1~exp1 (178 versions)
  • every version up to 7.2.6-1: fixed in 7.2.6-1
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Data Freshness Timeline

(refreshed 12× in last 7d / 41× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 1 repeat row among the latest 45 is merged into the row it repeats.

  1. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  2. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  3. 2026-10-12 14:57 UTCEG score recompute
  4. 2026-10-11 19:21 UTCEG score recompute
  5. 2026-10-11 16:37 UTCEG score recompute
  6. 2026-10-11 13:55 UTCEG score recompute
  7. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  8. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  9. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  10. 2026-10-09 19:24 UTCGHSA enrichmentGHSA-w44c-cv6c-x94c
  11. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  12. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  13. 2026-10-06 16:38 UTCGHSA enrichmentGHSA-w44c-cv6c-x94c
  14. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  15. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  16. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  17. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  18. 2026-10-03 14:11 UTCGHSA enrichmentGHSA-w44c-cv6c-x94c
  19. 2026-10-02 17:57 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  20. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  21. 2026-09-30 15:04 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  22. 2026-09-30 11:44 UTCEG score recompute
  23. 2026-09-30 11:44 UTCGHSA enrichmentGHSA-w44c-cv6c-x94c
  24. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  25. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.2% · 9th percentile
Show 19 more
  1. 2026-09-27 09:17 UTCGHSA enrichmentGHSA-w44c-cv6c-x94c
  2. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  3. 2026-09-26 00:28 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  4. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  5. 2026-09-24 06:49 UTCGHSA enrichmentGHSA-w44c-cv6c-x94c
  6. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  7. 2026-09-22 16:01 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  8. 2026-09-21 21:09 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  9. 2026-09-21 04:22 UTCGHSA enrichmentGHSA-w44c-cv6c-x94c
  10. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  11. 2026-09-18 01:54 UTCGHSA enrichmentGHSA-w44c-cv6c-x94c
  12. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  13. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  14. 2026-09-15 03:12 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  15. 2026-09-14 23:27 UTCEG score recompute
  16. 2026-09-14 23:27 UTCGHSA enrichmentGHSA-w44c-cv6c-x94c
  17. 2026-09-11 20:36 UTCNVD update
  18. 2026-09-11 19:52 UTCEG score recompute
  19. 2026-09-11 19:49 UTCMITRE cvelistV5first tracked

Frequently asked(4)

What is CVE-2026-81009?
CVE-2026-81009 is a vulnerability whose severity is not yet rated; its CVE record was published on September 11, 2026. In the Linux kernel, the following vulnerability has been resolved: iouring/query: cap user size passed to copystructtouser iohandlequeryentry() clamps hdr.size for the inbound copyfrom_user() but keeps the original user value as usize. copystructto_user() uses that usize and, when it is larger…
When was the CVE record for CVE-2026-81009 published?
The CVE record for CVE-2026-81009 was published on September 11, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of September 11, 2026; the record at its source may have been updated since.
Is CVE-2026-81009 actively exploited?
CVE-2026-81009 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (5th percentile of EPSS-scored CVEs).
How do I remediate CVE-2026-81009?
A fix for CVE-2026-81009 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-81009 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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