# CVE-2026-122193: OS command injection in the example SSM documents in Trusted Remote Execution (REX)

Status: published. Published: 2026-11-06. Updated: 2026-11-06.

OS command injection in the example SSM document provisioning script in Trusted Remote Execution (REX) before 2026-07-28 might allow an authenticated remote user who is permitted to invoke the Rex-RO or Rex-RW SSM document to execute arbitrary commands as root on the managed instance, bypassing Cedar policy enforcement.



To remediate this issue, users should delete any Rex-RO and Rex-RW SSM documents created from the example script, in each account and Region where it was run.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- AWS / trusted-remote-execution: Version not specified (affected, custom). Source: CNA: AMZN

## Severity and prioritization

- CVSS 3.1: 9.9 (critical); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H; source: CNA: AMZN

- CVSS 4.0: 9.3 (critical); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:L/SA:N; source: CNA: AMZN

- CVSS 4.0: 9.3 (critical); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: ff89ba41-3aa1-4d27-914a-91399e9639e5

- CVSS 3.1: 9.9 (critical); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H; source: NVD: ff89ba41-3aa1-4d27-914a-91399e9639e5

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: exploitation none; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-78

## Exploit evidence

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

## References

- https://aws.amazon.com/security/security-bulletins/2026-173-aws/ (CNA: AMZN; vendor-advisory)

- https://github.com/trusted-remote-execution/trusted-remote-execution/security/advisories/GHSA-95g5-m242-wvhr (CNA: AMZN; third-party-advisory)

- https://aws.amazon.com/security/security-bulletins/2026-173-aws/ (ff89ba41-3aa1-4d27-914a-91399e9639e5)

- https://github.com/trusted-remote-execution/trusted-remote-execution/security/advisories/GHSA-95g5-m242-wvhr (ff89ba41-3aa1-4d27-914a-91399e9639e5)

## Provenance

- CNA: AMZN: https://www.cve.org/CVERecord?id=CVE-2026-122193; retrieved 2026-11-06; source updated 2026-11-06

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-122193; retrieved 2026-11-07; source updated 2026-11-06

Revision: 7240a2cc567d687f2c5a56edf47551340498aa1e42295f25659dc41e9631abbb

Canonical: https://y2.dev/cve/CVE-2026-122193

## Agent and API access

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- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.