Improper Authentication in Chitchatter by Jeremy Kahn
CVE-2026-118129

5.3MEDIUM

Key Information:

Vendor

Jeremyckahn

Status
Chitchatter
Vendor
CVE Published:
27 October 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-118129?

A vulnerability in Chitchatter's PostMessage Handler allows for improper authentication due to manipulation of the 'parentDomain' argument within the 'isConfigMessageEvent' function. This flaw poses a risk for remote exploitation, making it essential to apply the available patch promptly. The vendor has acted swiftly to address this issue, ensuring that a secure version is now available for users.

Affected Version(s)

Chitchatter f82538633813c854a81a8b2112a2f6ba17b39cbc

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-118129 - Proof of Concept

References

https://vuldb.com/vuln/427456
vdb-entrytechnical-description
https://vuldb.com/vuln/427456/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-118129
third-party-advisory

CVSS V4

Score:
5.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

chenhuanlin (VulDB User)
VulDB CNA Team
.