# CVE-2026-65652: temporalio/tchannel-go malformed checksum type causes process termination

> CVE-2026-65652: temporalio/tchannel-go malformed checksum type causes process termination. CVSS 8.7 (CVSS 4.0).

Canonical: https://rewindex.com/cve/CVE-2026-65652
Last updated: 2026-09-22T19:40:05Z

- Published: 2026-09-21 11:35 UTC · Updated: 2026-09-22 19:40 UTC · Assigner: Temporal
- CVSS: 8.7 (CVSS 4.0) · Severity: High
- EPSS: 0.71%, 53th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-129

## Description

github.com/temporalio/tchannel-go did not validate the one-byte checksum-type field in inbound TChannel call frames. A network peer that can reach a listener can complete the standard initialization handshake and send a call request with an unsupported checksum type. The parser uses that value as an index into a four-entry checksum pool, causing an unrecovered Go panic on the connection read goroutine and terminating the hosting process. This allows remote denial of service against applications that expose the listener to untrusted peers. The impact is limited to availability; no confidentiality or integrity impact was identified.

## Affected vendors and products

- Temporal Technologies, Inc.: temporalio/tchannel-go

## Tracked companies

- [Temporal Cloud](https://rewindex.com/company/temporal-cloud.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-65652)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-65652)
- [https://github.com/temporalio/tchannel-go/blob/8706a1ab5f617efd79dace7ab2d1d80cc1881df0/checksum.go\#L29-L93](https://github.com/temporalio/tchannel-go/blob/8706a1ab5f617efd79dace7ab2d1d80cc1881df0/checksum.go#L29-L93)
- [https://github.com/temporalio/tchannel-go/blob/8706a1ab5f617efd79dace7ab2d1d80cc1881df0/reqres.go\#L280-L295](https://github.com/temporalio/tchannel-go/blob/8706a1ab5f617efd79dace7ab2d1d80cc1881df0/reqres.go#L280-L295)
- [https://github.com/temporalio/tchannel-go/commit/0cb017f6870a8420695abeb9a4560d39dadc4e2e](https://github.com/temporalio/tchannel-go/commit/0cb017f6870a8420695abeb9a4560d39dadc4e2e)
- [https://github.com/temporalio/tchannel-go/commit/a6904155f628b9e602b7bc88ef489004a786f7f4](https://github.com/temporalio/tchannel-go/commit/a6904155f628b9e602b7bc88ef489004a786f7f4)
- [https://github.com/temporalio/tchannel-go/pull/14](https://github.com/temporalio/tchannel-go/pull/14)
- [https://github.com/temporalio/tchannel-go/tree/v1.22.1](https://github.com/temporalio/tchannel-go/tree/v1.22.1)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-65652 · Markdown: https://rewindex.com/cve/CVE-2026-65652.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-65652 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:05:07.806Z