# exfat: fix handling of damaged volume in exfat_create_upcase_table()

CVE record · `CVE-2026-93828`

- **Identifiers:** `CVE-2026-93828`
- **State:** Confirmed
- **Severity:** No CVSS score
- **Critical:** No
- **CNA:** Linux
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 24 Sept 2026
- **Updated:** 30 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 24 Sept 2026, 16:03 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

## Affected products, as the CNA wrote them

- Vendor: Linux. Product: Linux.
  - affected: `370e812b3ec190fa492c9fd5a80c38b086d105c0 to before 091ca992218105a050af0b863337e02a2d518b2f` (git)
  - affected: `370e812b3ec190fa492c9fd5a80c38b086d105c0 to before 29723256fccf46e55c2a44bd6b8345bef7ba079b` (git)
  - affected: `370e812b3ec190fa492c9fd5a80c38b086d105c0 to before 60ace93811609e4dd883e9de5fb4462ed834160a` (git)
  - affected: `370e812b3ec190fa492c9fd5a80c38b086d105c0 to before 2cc0b612343638057ef321ce735201a7c2f52f25` (git)
  - affected: `370e812b3ec190fa492c9fd5a80c38b086d105c0 to before 20dd3185d13865214ff25b0bf7b931e8d73be1ac` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `5.7`
  - unaffected: `before 5.7` (semver)
  - unaffected: `6.1.191 to 6.1.*, inclusive` (semver)
  - unaffected: `6.6.160 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.111 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.53 to 6.18.*, inclusive` (semver)
  - unaffected: `7.2 to *, inclusive` (original_commit_for_fix)
  - Other versions: affected

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> The Linux kernel exFAT filesystem driver (exfat) is affected in multiple version ranges, starting from commit 370e812b3ec1 and fixed in several stable branches. A damaged or misbehaving volume whose upcase table size is recorded as zero can cause an integer overflow that makes the module loop indefinitely. The source does not describe what an attacker must do to trigger this beyond supplying such a volume. Upgrade to a fixed kernel version for your branch, such as 6.1.191, 6.6.160, 6.12.111, or 6.18.53 or later, or to a release containing the fix.

Written 12 Nov 2026.

## Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

## Severity and exploitation

No source has published a CVSS score for this record yet.

- **CISA KEV:** Not listed.
- **EPSS:** 0.0017, the 6th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

This record came from the full history of the CVE Program, published 24 Sept 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-93828](https://www.cve.org/CVERecord?id=CVE-2026-93828)
- [NVD: CVE-2026-93828](https://nvd.nist.gov/vuln/detail/CVE-2026-93828)

### References from the CNA

- <https://git.kernel.org/stable/c/091ca992218105a050af0b863337e02a2d518b2f>
- <https://git.kernel.org/stable/c/29723256fccf46e55c2a44bd6b8345bef7ba079b>
- <https://git.kernel.org/stable/c/60ace93811609e4dd883e9de5fb4462ed834160a>
- <https://git.kernel.org/stable/c/2cc0b612343638057ef321ce735201a7c2f52f25>
- <https://git.kernel.org/stable/c/20dd3185d13865214ff25b0bf7b931e8d73be1ac>

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.

## Check whether this affects you

This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it. Compare the affected versions above with what you run.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), `get_advisory` returns this record and `search_advisories` finds related ones. Setup: <https://agentprime.io/mcp.md>
- As JSON: <https://api.agentprime.io/v1/advisories/CVE-2026-93828>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-93828/>. Everything for agents: <https://agentprime.io/llms.txt>.
