CVE-2026-115778

HIGH
MEDIUM Priority: 0.04 BB Relevance: 75/100
Published: 2026-10-23 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: None
I: None
A: High

Description

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.

Weakness Classification (2)

Bug Bounty Relevance

75 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

7.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploitation Probability

0.54%
Raw Score 0.005400
Percentile 45.4%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00540
2026-10-28
0.00540

Intelligence Sources

nvd ref →