CVE-2026-123271: diillson ChatCLI · Origin Validation Error
Affects diillson ChatCLISource CVE Database V5
Not known to be exploited · CVSS 5.1 Medium : upgrade to v1.215.2 when convenient.
Data as of 5 Nov 2026, 19:05 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 5.1 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 8.0 |
- Patch
- Available – fixed in v1.215.2, 1.215.2
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 5 Nov 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 ChatCLI to v1.215.2; ChatCLI to 1.215.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| diillsonChatCLI | Affected
| Fixed in
|
GoChatCLIpkg:golang/ChatCLIOther 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
Upgrade ChatCLI to version 1.215.2 or later, where the origin validation issue in the MCP OAuth login flow is fixed. No other mitigation is necessary as the vulnerability is addressed in this official fix.
Description
ChatCLI versions before 1.215.2 have an origin validation vulnerability in the MCP OAuth login flow. The flaw involves improper validation of server-supplied Protected Resource Metadata, allowing a malicious MCP server to misuse bearer tokens by declaring unauthorized resources on the same authorization server. This can lead to token replay attacks against unintended resources.
References
- github.com/diillson/chatcli/security/advisories/GHSA-95vg-3r9c-2v5q (opens in a new tab)
- github.com/diillson/chatcli/commit/951fe24b8e090eae86bf8edb13a788916b1e6c91 (opens in a new tab)
- github.com/diillson/chatcli/releases/tag/v1.215.2 (opens in a new tab)
- github.com/diillson/chatcli/blob/359eb27debc4de78289a9662551a51ab4528e16c/cli/mcp/oauth.go (opens in a new tab)
- vulncheck.com/advisories/chatcli-before-1.215.2-origin-validation-error-via-unvalidated-mcp-oauth-resource-indicator (opens in a new tab)