# vsock/virtio: validate packet source for connected sockets

CVE record · `CVE-2026-99123`

- **Identifiers:** `CVE-2026-99123`
- **State:** Confirmed
- **Severity:** CVSS 7.1 High
- **Critical:** No
- **CNA:** Linux
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 28 Oct 2026
- **Updated:** 31 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 28 Oct 2026, 10:34 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: `06a8fc78367d070720af960dcecec917d3ae5f3b to before bda841af86cdfe7fcf4a2f4db22e27f1b852b1ff` (git)
  - affected: `06a8fc78367d070720af960dcecec917d3ae5f3b to before c0a3a786a5e8b5007d6a3c34721ab052399ab2ad` (git)
  - affected: `06a8fc78367d070720af960dcecec917d3ae5f3b to before f77fb90edca5385d0eecbfd6d2c8ef60afff24a9` (git)
  - affected: `06a8fc78367d070720af960dcecec917d3ae5f3b to before ec231dd3b14e541ba1c4f842a7d152fb61037333` (git)
  - affected: `06a8fc78367d070720af960dcecec917d3ae5f3b to before 6cd829de69efd9ed3a53aa2421004a0396eb2bd7` (git)
  - affected: `06a8fc78367d070720af960dcecec917d3ae5f3b to before e9bf92de436ba55f33eaa55d7008e68551123cfd` (git)
  - affected: `06a8fc78367d070720af960dcecec917d3ae5f3b to before dee44f41f206becb41c492899c1996cfd7f82a1b` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `4.8`
  - unaffected: `before 4.8` (semver)
  - unaffected: `5.15.224 to 5.15.*, inclusive` (semver)
  - unaffected: `6.1.191 to 6.1.*, inclusive` (semver)
  - unaffected: `6.6.161 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.115 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.59 to 6.18.*, inclusive` (semver)
  - unaffected: `7.2.13 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

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

- **CISA KEV:** Not listed.
- **EPSS:** 0.0013, the 2nd percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 28 Oct 2026, 10:34 UTC: [Confirmed by the CVE List](https://www.cve.org/CVERecord?id=CVE-2026-99123)

## Sources

- [CVE List: CVE-2026-99123](https://www.cve.org/CVERecord?id=CVE-2026-99123)
- [NVD: CVE-2026-99123](https://nvd.nist.gov/vuln/detail/CVE-2026-99123)

### References from the CNA

- <https://git.kernel.org/stable/c/bda841af86cdfe7fcf4a2f4db22e27f1b852b1ff>
- <https://git.kernel.org/stable/c/c0a3a786a5e8b5007d6a3c34721ab052399ab2ad>
- <https://git.kernel.org/stable/c/f77fb90edca5385d0eecbfd6d2c8ef60afff24a9>
- <https://git.kernel.org/stable/c/ec231dd3b14e541ba1c4f842a7d152fb61037333>
- <https://git.kernel.org/stable/c/6cd829de69efd9ed3a53aa2421004a0396eb2bd7>
- <https://git.kernel.org/stable/c/e9bf92de436ba55f33eaa55d7008e68551123cfd>
- <https://git.kernel.org/stable/c/dee44f41f206becb41c492899c1996cfd7f82a1b>

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-2026-99123>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-99123/>. Everything for agents: <https://agentprime.io/llms.txt>.