# md: do overflow check for sb->bblog_shift in super_1_load()

CVE record · `CVE-2026-89557`

- **Identifiers:** `CVE-2026-89557`
- **State:** Confirmed
- **Severity:** CVSS 7.8 High
- **Critical:** No
- **CNA:** Linux
- **Technologies:** [Linux kernel](https://agentprime.io/advisories/technology/linux-kernel.md)
- **Published:** 11 Sept 2026
- **Updated:** 19 Oct 2026
- **Reviewed by a person:** No

Published by the CVE Program (CNA: Linux) at 11 Sept 2026, 19:44 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: `2699b67223aca6b1450fc2f72e40fada952afc85 to before 94c820d99a4305d4ded41a97ed37ec7d26c56e7f` (git)
  - affected: `2699b67223aca6b1450fc2f72e40fada952afc85 to before 573fb68105fdc6a127ba6069e58a0d2aff3c9f93` (git)
  - affected: `2699b67223aca6b1450fc2f72e40fada952afc85 to before 323f3a056dbccb39a642ebde642044a680f3a6d6` (git)
  - affected: `2699b67223aca6b1450fc2f72e40fada952afc85 to before 0a03f9541c06fda64301dcf94f376f07ce2cc396` (git)
  - affected: `2699b67223aca6b1450fc2f72e40fada952afc85 to before 75d15738fd33a782606d0dc80cfeff47edf2ddd8` (git)
  - affected: `2699b67223aca6b1450fc2f72e40fada952afc85 to before 3b097416b4cff77285c1f472fc2c4058d8a7554f` (git)
  - affected: `2699b67223aca6b1450fc2f72e40fada952afc85 to before df7d4d011d5ace20699ea948712f09f9ac08924f` (git)
  - affected: `2699b67223aca6b1450fc2f72e40fada952afc85 to before 35d522bd32462afcf1981dab6da8a9256c26c1e0` (git)
  - Other versions: unaffected
- Vendor: Linux. Product: Linux.
  - affected: `3.1`
  - unaffected: `before 3.1` (semver)
  - unaffected: `5.10.270 to 5.10.*, inclusive` (semver)
  - unaffected: `5.15.221 to 5.15.*, inclusive` (semver)
  - unaffected: `6.1.188 to 6.1.*, inclusive` (semver)
  - unaffected: `6.6.157 to 6.6.*, inclusive` (semver)
  - unaffected: `6.12.109 to 6.12.*, inclusive` (semver)
  - unaffected: `6.18.50 to 6.18.*, inclusive` (semver)
  - unaffected: `7.2.4 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

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

- **CISA KEV:** Not listed.
- **EPSS:** 0.0017, the 6th percentile, on 14 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 11 Sept 2026. New records show when each source confirmed them.

## Sources

- [CVE List: CVE-2026-89557](https://www.cve.org/CVERecord?id=CVE-2026-89557)
- [NVD: CVE-2026-89557](https://nvd.nist.gov/vuln/detail/CVE-2026-89557)

### References from the CNA

- <https://git.kernel.org/stable/c/94c820d99a4305d4ded41a97ed37ec7d26c56e7f>
- <https://git.kernel.org/stable/c/573fb68105fdc6a127ba6069e58a0d2aff3c9f93>
- <https://git.kernel.org/stable/c/323f3a056dbccb39a642ebde642044a680f3a6d6>
- <https://git.kernel.org/stable/c/0a03f9541c06fda64301dcf94f376f07ce2cc396>
- <https://git.kernel.org/stable/c/75d15738fd33a782606d0dc80cfeff47edf2ddd8>
- <https://git.kernel.org/stable/c/3b097416b4cff77285c1f472fc2c4058d8a7554f>
- <https://git.kernel.org/stable/c/df7d4d011d5ace20699ea948712f09f9ac08924f>
- <https://git.kernel.org/stable/c/35d522bd32462afcf1981dab6da8a9256c26c1e0>

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-2026-89557>
- Everything that needs attention now: <https://agentprime.io/advisories/critical.md>

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The web page: <https://agentprime.io/advisories/CVE-2026-89557/>. Everything for agents: <https://agentprime.io/llms.txt>.