CVE intelligence

CVE-2026-115778

Vulnerability intelligence

Published Oct 23, 2026Sources checked Oct 29, 2026

7.5HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-115778 and is rated High severity with a CVSS score of 7.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Oct 29, 2026

Release Notes

CISA KEVNot listedBased on the latest collected catalog

EPSS0.5%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-115778?

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.10.0rc1, twisted.conch.telnet.Telnet.dataReceived appends every byte received after IAC SB to a persistent subnegotiation buffer until IAC SE is received, without applying a maximum length.

Telnet option negotiation occurs before authentication, so an unauthenticated peer can omit the terminator and continuously grow the buffer. The resulting memory exhaustion can terminate the process and every service it hosts.

This issue is fixed in version 26.10.0rc1.

Source: NVD