# ksmbd: fix heap out-of-bounds write in krb5_authenticate()

CVE record · `CVE-2026-99083`

- **Identifiers:** `CVE-2026-99083`
- **State:** Confirmed
- **Severity:** CVSS 8.8 High
- **Critical:** No
- **CNA:** Linux
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 23 Oct 2026
- **Updated:** 30 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 23 Oct 2026, 12:45 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: `676392184785ace61e939831e7ca44a03d438c3b to before a07dfb33112a42437f9d2d0bfd35c68575257381` (git)
  - affected: `ef572ffa8eb44111eed2925fbb2adca78bdcbf61 to before 1f73a6d40f4d1bae4f3491c0ec1ea8ee6ce035ff` (git)
  - affected: `98422bdd4cb3ca4d08844046f6507d7ec2c2b8d8 to before 59c6dcc5dd9dafe764ca0d40525933b2be69b059` (git)
  - affected: `98422bdd4cb3ca4d08844046f6507d7ec2c2b8d8 to before 80af1bde97d5a85ad6f2c40ca894ccc8fa75a27a` (git)
  - affected: `98422bdd4cb3ca4d08844046f6507d7ec2c2b8d8 to before 517404e157395d0f8da125ca956c566895dfcd06` (git)
  - affected: `98422bdd4cb3ca4d08844046f6507d7ec2c2b8d8 to before 4722d06b2907585074252061b1024a696c1cfc23` (git)
  - affected: `98422bdd4cb3ca4d08844046f6507d7ec2c2b8d8 to before 23a0be6a84a38ac169eeab49017934e8e27c65f0` (git)
  - affected: `2ba03cecb12ac7ac9e0170e251543c56832d9959` (git)
  - affected: `5.15.145 to before 5.15.224` (semver)
  - affected: `6.1.40 to before 6.1.191` (semver)
  - affected: `6.4.5 to before 6.5` (semver)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `6.5`
  - unaffected: `before 6.5` (semver)
  - unaffected: `5.15.224 to 5.15.*, inclusive` (semver)
  - unaffected: `6.1.191 to 6.1.*, inclusive` (semver)
  - unaffected: `6.6.160 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.114 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.58 to 6.18.*, inclusive` (semver)
  - unaffected: `7.2.12 to 7.2.*, inclusive` (semver)
  - unaffected: `7.3 to *, inclusive` (original_commit_for_fix)
  - Other versions: affected

## 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

- 8.8 High, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`, from CNA (Linux)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0044, the 38th percentile, on 5 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 23 Oct 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-99083](https://www.cve.org/CVERecord?id=CVE-2026-99083)
- [NVD: CVE-2026-99083](https://nvd.nist.gov/vuln/detail/CVE-2026-99083)

### References from the CNA

- <https://git.kernel.org/stable/c/a07dfb33112a42437f9d2d0bfd35c68575257381>
- <https://git.kernel.org/stable/c/1f73a6d40f4d1bae4f3491c0ec1ea8ee6ce035ff>
- <https://git.kernel.org/stable/c/59c6dcc5dd9dafe764ca0d40525933b2be69b059>
- <https://git.kernel.org/stable/c/80af1bde97d5a85ad6f2c40ca894ccc8fa75a27a>
- <https://git.kernel.org/stable/c/517404e157395d0f8da125ca956c566895dfcd06>
- <https://git.kernel.org/stable/c/4722d06b2907585074252061b1024a696c1cfc23>
- <https://git.kernel.org/stable/c/23a0be6a84a38ac169eeab49017934e8e27c65f0>

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-2026-99083>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-99083/>. Everything for agents: <https://agentprime.io/llms.txt>.