8.7
HIGH CVSS 4.0
CVE-2026-65653
temporalio/tchannel-go zero-chunk call fragment causes process termination
Description

github.com/temporalio/tchannel-go did not reject TChannel call fragments containing checksum metadata but no length-prefixed argument chunks. The fragment reader left its chunk slice empty and then unconditionally selected the first element. A network peer can supply such a malformed call fragment, including as a direct initial call request after completing the standard initialization handshake. On that inbound path, the resulting unrecovered Go slice-bounds panic occurs on a library-created dispatch goroutine and terminates 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.

INFO

Published Date :

Sept. 21, 2026, 12:17 p.m.

Last Modified :

Sept. 21, 2026, 12:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-65653 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 HIGH 61241ed8-fa44-4f23-92db-b8c443751968
CVSS 4.0 HIGH [email protected]
Solution
Update the TChannel Go library to fix a crash vulnerability in chunk handling.
  • Update the TChannel Go library to the latest version.
  • Ensure the library handles malformed call fragments gracefully.
  • Validate incoming data for correct chunk structure.
  • Restart affected applications after updating.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-65653 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-65653 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-65653 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-65653 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 21, 2026

    Action Type Old Value New Value
    Added Description github.com/temporalio/tchannel-go did not reject TChannel call fragments containing checksum metadata but no length-prefixed argument chunks. The fragment reader left its chunk slice empty and then unconditionally selected the first element. A network peer can supply such a malformed call fragment, including as a direct initial call request after completing the standard initialization handshake. On that inbound path, the resulting unrecovered Go slice-bounds panic occurs on a library-created dispatch goroutine and terminates 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/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
    Added CWE CWE-129
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/65xxx/CVE-2026-65653.json">CVE-2026-65653</a>
    Added Reference https://github.com/temporalio/tchannel-go/blob/8706a1ab5f617efd79dace7ab2d1d80cc1881df0/fragmenting_reader.go#L256-L308
    Added Reference https://github.com/temporalio/tchannel-go/commit/0cb017f6870a8420695abeb9a4560d39dadc4e2e
    Added Reference https://github.com/temporalio/tchannel-go/commit/1dcfa67262ecd56a24f12940f4082549190cb5d1
    Added Reference https://github.com/temporalio/tchannel-go/commit/8d8ca17342b3620d3a6d5c1a825145595e7588ff
    Added Reference https://github.com/temporalio/tchannel-go/pull/14
    Added Reference https://github.com/temporalio/tchannel-go/tree/v1.22.1
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.