# iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails

CVE record · `CVE-2021-47327`

- **Identifiers:** `CVE-2021-47327`
- **State:** Confirmed
- **Severity:** CVSS 7.1 High
- **Critical:** No
- **CNA:** Linux
- **Weakness (CWE):** [CWE-911](https://cwe.mitre.org/data/definitions/911.html)
- **Tags:** [CWE-911](https://agentprime.io/advisories/tag/cwe-911.md)
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 21 May 2024
- **Updated:** 11 May 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 21 May 2024, 14:35 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: `d4a44f0750bb9bf7c44c22444a482756b2344a79 to before 3761ae0d0e549f2acdaf11f49df4ed06d256b20f` (git)
  - affected: `d4a44f0750bb9bf7c44c22444a482756b2344a79 to before c4007596fbdabc29f858dc2e1990858a146b60b2` (git)
  - affected: `d4a44f0750bb9bf7c44c22444a482756b2344a79 to before fbf4daa6f4105e01fbd3868006f65c163365c1e3` (git)
  - affected: `d4a44f0750bb9bf7c44c22444a482756b2344a79 to before fe92c058199067ae90cf2a901ddf3c271893557a` (git)
  - affected: `d4a44f0750bb9bf7c44c22444a482756b2344a79 to before 1adf30f198c26539a62d761e45af72cde570413d` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `5.0`
  - unaffected: `before 5.0` (semver)
  - unaffected: `5.4.134 to 5.4.*, inclusive` (semver)
  - unaffected: `5.10.52 to 5.10.*, inclusive` (semver)
  - unaffected: `5.12.19 to 5.12.*, inclusive` (semver)
  - unaffected: `5.13.4 to 5.13.*, inclusive` (semver)
  - unaffected: `5.14 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:H/I:N/A:H`, from ADP (CISA-ADP)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0026, the 17th 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 21 May 2024. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2021-47327](https://www.cve.org/CVERecord?id=CVE-2021-47327)
- [NVD: CVE-2021-47327](https://nvd.nist.gov/vuln/detail/CVE-2021-47327)

### References from the CNA

- <https://git.kernel.org/stable/c/3761ae0d0e549f2acdaf11f49df4ed06d256b20f>
- <https://git.kernel.org/stable/c/c4007596fbdabc29f858dc2e1990858a146b60b2>
- <https://git.kernel.org/stable/c/fbf4daa6f4105e01fbd3868006f65c163365c1e3>
- <https://git.kernel.org/stable/c/fe92c058199067ae90cf2a901ddf3c271893557a>
- <https://git.kernel.org/stable/c/1adf30f198c26539a62d761e45af72cde570413d>

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-2021-47327>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2021-47327/>. Everything for agents: <https://agentprime.io/llms.txt>.