vciy

CVE-2026-93834

INDEX BUILT · 2026-10-18

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Qemu-kvm: 9pfs: use-after-free race in tlcreate/twalk allows vm guest escape

CVE-2026-938343 of 4 sources documented this
37

rank 37 = 15 + 22 + 0 + 0 + 0

rank@v1 · scheduled

Someone is already using it

CISA KEV catalog · public proof-of-concept · FIRST EPSS

EPSS 0.00377  ·  without this subject the record ranks 22

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 8.8, from NVD  ·  without this subject the record ranks 15

It is getting worse, not staying still

FIRST EPSS series, rescorings and bad loads removed

no persisting rise in 365 days  ·  without this subject the record ranks 37

How much of the world it touches

NVD CPE configurations

0 products in the CPE ranges  ·  without this subject the record ranks 37

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 37

Hindsight · the state

0.00377EPSSNOT IN KEVas of 2026-10-18
Severity8.8 HIGHreceipt
Harmtotal lossreceipt
Exploitationpublic proof-of-conceptreceipt
Defenseno fix version held
Movementone observationreceipt
SINGLE READINGOne observation held. There is no shape yet. arc-rules@v1

Foresight · where to check next

Microsoft WindowsLinux KernelMicrosoft WindowsMicrosoft Windows93834

This record is one instance of CWE-416, use after free. The index holds 9292 prior instances of this class, 106 KEV-listed. The nearest of its KEV-listed records are drawn beside this. taxonomy@v1

Full pattern panel

Prior records in this weakness class. Each is its own record, dated and receipted.
Color is a claim, not decoration:the hostile worldthe defenseno signalspoke length is how much of the record matches, not how bad it is

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Harm, if it fires from the vector and the weakness

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Reachneeds local access · low privileges required · no user interaction · low attack complexityreceipt
ImpactComplete confidentiality, integrity and availability loss, with impact beyond the vulnerable componentreceipt
Scored fromCVSS v3.1 · the CNA's vectorreceipt
Weakness classCWE-416 Use After Freereceipt
Published consequencesCWE-416: Integrity: Modify Memory; Availability: DoS: Crash, Exit, or Restart; Confidentiality: Read Memory; Integrity, Confidentiality, Availability: Execute Unauthorized Code or Commandscwe-consequences@4.20

CISA KEV & Federal Remediation Deadline from the record and CISA

The fix, and how long it's been waiting.

Fixed inNo fix version in held sources, as the index stood on 28 Sep 2026.
Patch available sinceNo dated patch-availability record in held sources. The index holds reference URLs without dates and only the current revision of the CVE record, so the day a fix first existed cannot be derived. Only the versions it landed in.
BOD 26-04 deadlineIf the system is reachable from the internet: 14 days. If not: fix at the next system upgrade.derived
Show full BOD 26-04 deadline

CISA has not scored it, so the directive's own defaults apply: automatable no, technical impact total. Calendar days from the KEV listing or from when you find it on a system, whichever is first. Federal agencies are bound from 7 Dec 2026, and contracts often carry it to suppliers. The directive and its table

Exploit Status & Known PoCs a ladder, not a score

Current rung: Proof-of-concept published · 1 public repository, 2026-09-26.

  • RUNG 1Nothing observed in held sources
  • RUNG 2Proof-of-concept published · 1 public repository2026-09-26receipt
  • RUNG 3Exploited in the wild · CISA KEV listed
  • RUNG 4Ransomware campaign use known

Authority who says so

CVSS, the CNA8.8 HIGHreceipt
CVSS, NVD8.8 HIGHreceipt
Exploit probability0.00377 · top 70% of all CVEsreceipt
Assigned byredhatreceipt
Recorded changes4 · last 18 Oct 2026derived

Affected & Fixed Versions as published

Affected productRed Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat Enterprise Linux for NVIDIA 26…receipt

A rung lights from a row in the index, never from an assessment. "Held sources" is the true scope of the claim: this index reads the CVE record, NVD, CISA KEV, FIRST's EPSS and public proof-of-concept repositories, and it does not observe attacks.

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$18,800over the next 30 days, if this record is yours
Movementnot heldno dated series to read a change from
Basisassumeda published average, not your estate

$18,800 = $4.99M incident cost x 1 exposure x 0.00377 likelihood

udv@v1 · unaudited · wrong for you until you say what you run

$4.99M is the cost of a breach that happened, from IBM Cost of a Data Breach Report 2026, global average. It is not the value of any asset of yours. That average already covers breaches of every severity, so scaling it by exposure understates a partial-impact record. That is an assumption, not a measurement. Your own asset value goes in the decision record.

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Attack path

Local accessrequires low privilegesRed Hat Enterprise Linux 6CWE-416 use after freeAdjacent componentsscope changeFull compromise (C/I/A)C:H / I:H / A:Hexploits CWE-416scope changedata compromise

What it is stated by the CNA

A use-after-free vulnerability was found in QEMU's 9pfs subsystem. A race condition between the main thread and a worker thread when processing concurrent Tlcreate and Twalk requests allows a malicious guest user to craft a fid path containing stale heap data, bypassing directory traversal restrictions and escaping the shared directory boundary. This can lead to arbitrary host file read/write and code execution (VM escape) as the QEMU process user. receipt

NVD's analysis a second authority

severity
8.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
weakness
CWE-416

check it yourself access.redhat.com bugzilla.redhat.com gitlab.com receipt

Movement

Only one observation of this value is held, so there is no movement to show yet.

The full biography

Published2026-09-25Public PoC2026-09-26Index as of2026-09-28

The record had been public for 3 days when this index was last written.

Published 2026-09-25 receipt · Public PoC 2026-09-26 receipt · Index as of 2026-09-28 derived

The pattern, elsewhere

This record is one instance of CWE-416, use after free. The index holds 9292 prior instances of this class, 106 KEV-listed. The nearest of its KEV-listed records are drawn beside this. cwe-consequences@4.20

CVE-2025-29824 · Microsoft Windows 10 Version 1507matches 7 of 9KEV listed · 2025receipt
CVE-2024-1086 · Linux Kernelmatches 7 of 9KEV listed · 2024receipt
CVE-2021-40449 · Microsoft Windows 10 Version 1809matches 7 of 9KEV listed · 2021receipt
CVE-2025-21334 · Microsoft Windows 10 Version 21H2matches 7 of 9KEV listed · 2025receipt
CVE-2025-21335 · Microsoft Windows 10 Version 21H2matches 7 of 9KEV listed · 2025receipt
CVE-2025-30400 · Microsoft Windows 10 Version 1809matches 7 of 9KEV listed · 2025receipt

"Matches n of m" counts the attributes the two records can both be compared on: the CVSS metrics they share a version of, any weakness class beyond this one, and the vendor. fit-rules@v1

9292 records in this class held. The six above are drawn from the ones CISA has listed as exploited, ranked by how much of the record matches this one. That is why every one of them is KEV-listed: the pool is, so the colour on those spokes says nothing the pool has not already said.

No curated product neighbourhood is held for this product, so the records above are the nearest this index can name. The neighbourhood table covers a small set of products and is extended by hand.

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