UPX - Tool

Threat entity extracted from intelligence sources

Frequency
9
occurrences
First Seen
December 3, 2025
Last Seen
July 24, 2026

UPX, the Ultimate Packer for eXecutables, is a widely used open-source binary packer that compresses executables to reduce size and obscure contents.

UPX is a tool tracked across 7 threat clusters and 9 intelligence report mentions on ThreatCluster. First observed December 3, 2025; most recent activity July 24, 2026.

Overview

UPX, the Ultimate Packer for eXecutables, is a widely used open-source binary packer that compresses executables to reduce size and obscure contents. In threat operations, attackers routinely leverage packers to shrink payloads and hinder static analysis, making UPX-packed binaries a notable tactic in malware campaigns and exploit deliveries.

Related Threat Clusters

Recent Intelligence Reports

  • Analysis Of Kimsuky S Attack On A South Korean Groupware Vendor Using A New Gomir Family Variant — www.enki.co.kr · July 24, 2026
  • Claroty's Team82 identified IOCONTROL — claroty.com · July 24, 2026
  • Check Point — research.checkpoint.com · June 17, 2026
  • Zero — Thecyberexpress · February 18, 2026
  • China-linked snoops have been exploiting Dell 0-day since mid-2024, using 'ghost NICs' to avoid detection — Theregister · February 18, 2026
  • Increased stealth integrated into flexible pkr_mtsi malware loader — Scworld · January 8, 2026
  • Versatile Malware Loader pkr_mtsi Delivers Diverse Payloads — Infosecurity-Magazine · January 7, 2026
  • Gogs Zero-Day RCE (CVE-2025-8110) Actively Exploited — Wiz · December 10, 2025

Frequently asked questions

What is UPX?

UPX, the Ultimate Packer for eXecutables, is a widely used open-source binary packer that compresses executables to reduce size and obscure contents.

Is UPX still active?

The most recent intelligence report mentioning UPX on ThreatCluster is dated July 24, 2026. Activity was first observed December 3, 2025, giving a tracked span from then to July 24, 2026.

What is UPX associated with?

Across ThreatCluster reporting, UPX most frequently co-occurs with CyberAv3ngers, Gonjeshke Darande, Kimsuky, Silver Fox APT, Unc6201, among 12 tracked related entities.

What are the latest developments involving UPX?

The most significant recent cluster is “Iranian Hackers Target U.S. Critical Infrastructure with Advanced PLC Attacks” (17 articles · Updated July 23, 2026). UPX appears across 7 threat clusters in total, listed above with sources.

How much reporting does ThreatCluster have on UPX?

UPX appears in 9 intelligence report mentions across 7 deduplicated threat clusters, aggregated from 17,000+ monitored sources.

CVSS v3.1 Breakdown