CVE-2026-65652: Temporal Technologies temporalio/tchannel-go · Improper Validation of Array Index
Affects Temporal Technologies temporalio/tchannel-goSource CVE Database V5
Not known to be exploited · CVSS 8.7 High : upgrade to 1.22.1-0.20260720194454-0cb017f6870a soon.
Data as of 5 Nov 2026, 23:24 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 53% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.22.1-0.20260720194454-0cb017f6870a
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 21 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade temporalio/tchannel-go and github.com/temporalio/tchannel-go to 1.22.1-0.20260720194454-0cb017f6870a.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Temporal Technologies, Inc.temporalio/tchannel-go | Affected
| Fixed in
|
Gogithub.com/temporalio/tchannel-gopkg:golang/github.com/temporalio/tchannel-goOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, restrict network access to the listener to trusted peers only to reduce exposure to untrusted attackers.
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.
References
- github.com/temporalio/tchannel-go/commit/a6904155f628b9e602b7bc88ef489004a786f7f4 (opens in a new tab)
- github.com/temporalio/tchannel-go/blob/8706a1ab5f617efd79dace7ab2d1d80cc1881df0/reqres.go (opens in a new tab)
- github.com/temporalio/tchannel-go/blob/8706a1ab5f617efd79dace7ab2d1d80cc1881df0/checksum.go (opens in a new tab)
- github.com/temporalio/tchannel-go/pull/14 (opens in a new tab)
- github.com/temporalio/tchannel-go/commit/0cb017f6870a8420695abeb9a4560d39dadc4e2e (opens in a new tab)
- github.com/temporalio/tchannel-go/tree/v1.22.1 (opens in a new tab)