# CVE-2026-65843: sync-rpc: Arbitrary remote code execution vulnerability

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

sync-rpc runs asynchronous commands synchronously by putting them in a separate proces. Prior to version 1.3.7, if an attacker could guess the correct port and it was not blocked via a firewall, it was possible to load and execute arbitrary JavaScript files stored on the server running sync-rpc. This issue has been patched in version 1.3.7.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- ForbesLindesay / sync-rpc: < 1.3.7 (affected). Source: CNA: GitHub_M

## Severity and prioritization

- CVSS 4.0: 8.7 (high); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N; source: CNA: GitHub_M

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-306

## Exploit evidence

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

## References

- https://github.com/ForbesLindesay/sync-rpc/security/advisories/GHSA-2x86-cf3f-86gw (CNA: GitHub_M; x_refsource_CONFIRM)

- https://github.com/ForbesLindesay/sync-rpc/commit/ffccfe5bc39ad2e291a79c9e5afe6155ad311f07 (CNA: GitHub_M; x_refsource_MISC)

## Provenance

- CNA: GitHub_M: https://www.cve.org/CVERecord?id=CVE-2026-65843; retrieved 2026-11-11; source updated 2026-11-11

Revision: e775cc29651c9cc04b0142a7b3447a6d5ccf9b76619c96d9c6bed6aa4bc4c0be

Canonical: https://y2.dev/cve/CVE-2026-65843

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