# CVE-2026-122192: Guest access to Firecracker process memory after a failed memory discard

Status: published. Published: 2026-11-04. Updated: 2026-11-04.

Improper handling of a failed memory remap in Firecracker versions 0.23.0 through 1.16.1 might allow a guest user with root privileges to read or modify Firecracker VMM process memory via balloon or virtio-mem discard requests on microVMs restored from a snapshot with the File memory backend, if the host fails to create the replacement mapping.



To remediate this issue, users should upgrade to Firecracker 1.16.2 or 1.17.0 and later.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: AMZN) — https://github.com/firecracker-microvm/firecracker/releases/tag/v1.16.2
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: AMZN) — https://github.com/firecracker-microvm/firecracker/releases/tag/v1.17.0

## Affected products and versions

- AWS / firecracker: ≥ 0.23.0; < 1.16.2 (affected, custom). Source: CNA: AMZN

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H; source: CNA: AMZN

- CVSS 4.0: 7.1 (high); CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N; source: CNA: AMZN

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-390, CWE-825

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/firecracker-microvm/firecracker/releases/tag/v1.16.2 (CNA: AMZN; release-notes, patch)

- https://github.com/firecracker-microvm/firecracker/releases/tag/v1.17.0 (CNA: AMZN; release-notes, patch)

- https://aws.amazon.com/security/security-bulletins/2026-169-aws/ (CNA: AMZN; vendor-advisory)

- https://github.com/firecracker-microvm/firecracker/security/advisories/GHSA-48ww-rqpp-2mgm (CNA: AMZN; third-party-advisory)

## Provenance

- CNA: AMZN: https://www.cve.org/CVERecord?id=CVE-2026-122192; retrieved 2026-11-04; source updated 2026-11-04

Revision: 2c2d6f42791fe7576144d4d645a895aeed08b19c901a4fa2a345c0b2ee9559dd

Canonical: https://y2.dev/cve/CVE-2026-122192

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