GCD AI RADAR
incidents/AIR-2025-0070

SesameOp Backdoor Abuses OpenAI Assistants API for C2

AI-enabled attack3 Confirmed exploitationOther

Threat actors utilized a backdoor implant called SesameOp to abuse the OpenAI Assistants API as a covert command and control channel. The malware fetched commands and exfiltrated encrypted results to maintain espionage persistence.

Details

type
AI-enabled attack
Attackers used AI as a meaningful part of a cyberattack against someone else.
categories
  • Other
    In scope, but none of the categories above fits. Reviewed periodically for new categories.
owasp llm top 10
no entry for these categories
mitre atlas
no technique for these categories
Both rows are derived from the type and categories (OWASP 2025 edition, ATLAS release 2026.09), not classified per record. How
severity
3 · Confirmed exploitation
Used against real targets; limited or unclear impact.
targets
OpenAI, Enterprise deployment
products
OpenAI Assistants API, SesameOp
incident date
Jul 2025 (approx.)
first reported
24 Dec 2025
origin
MITRE ATLAS
Derived from MITRE ATLAS (Apache 2.0, © MITRE).
classifier confidence
0.95 · published at or above 0.80; see the methodology
tags
sesameop · openai-api · c2-channel
record
created 2026-10-18 06:55Z · updated 2026-10-18 06:55Z · json

Sources · 2

  1. 2025-12-24
    SesameOp: Novel backdoor uses OpenAI Assistants API for command and control
    MITRE ATLAS · atlas.mitre.org/studies/AML.CS0042
  2. 2025-12-24
    SesameOp: Novel backdoor uses OpenAI Assistants API for command and control
    Microsoft Security · microsoft.com/en-us/security/blog/2025/11/03/sesameop-novel-backdoor-uses-openai

Titles and links belong to their publishers. The summary above is written by GCD AI RADAR in its own words; data is CC BY-SA 4.0.

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