ZeroHour

CVE-2025-8088

KEV ransomwaremass

WinRAR Path Traversal (CVE-2025-8088) Enables Arbitrary Code Execution

CISA: RARLAB WinRAR Path Traversal Vulnerability

CVSS 4.0
8.4 high
EPSS
95%p100
Published
()
KEV added
AI analysis

A path traversal flaw (CWE-35) in the Windows version of WinRAR allows attackers to achieve arbitrary code execution by delivering a specially crafted archive file that writes outside the expected location when it is opened or processed. Because the CVSS 4.0 vector indicates a local attack requiring user interaction, victims are typically infected by extracting or previewing a malicious archive received via phishing, a malicious download, or another delivery channel. A successful attacker gains the privileges of the user running WinRAR, providing an initial foothold that has been used for both espionage and ransomware operations. Anyone running the Windows version of WinRAR — one of the most widely deployed Windows desktop utilities — is affected, and CPE data additionally lists dtSearch as an affected vendor. Exploitation is confirmed in the wild by nation-state actors (e.g., the China-linked Amaranth-Dragon group per related reporting) and criminal actors including ransomware operators; the flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2025-08-12 and carries a near-maximal 94.6% EPSS score.

What to do: Update WinRAR to the latest patched release from RARLAB on all Windows endpoints, prioritizing remediation per CISA KEV and BOD 22-01 requirements, and verify that dtSearch deployments bundling the affected component are also updated. Because exploitation requires a user to open or extract a crafted archive, warn users to treat unexpected archive files delivered by email or download with suspicion. Given confirmed ransomware use, hunt across user workstations — not just exposed servers — for suspicious archive-based infections and confirm the patched WinRAR version is installed.

Affected
RARLAB WinRAR
dtsearch
Estimated exposure
masshundreds of millions of Windows users/devices (est.; RARLAB has historically claimed user counts in the hundreds of millions) — WinRAR is a near-ubiquitous Windows desktop archive utility with a vendor-advertised user base in the hundreds of millions, so unpatched desktop exposure is plausibly on the order of hundreds of millions of installs, well above the 'mass'…

Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.

Description

A path traversal vulnerability affecting the Windows version of WinRAR allows the attackers to execute arbitrary code by crafting malicious archive files. This vulnerability was exploited in the wild and was discovered by Anton Cherepanov, Peter Košinár, and Peter Strýček from ESET.

CISA Known Exploited Vulnerability
Affected
RARLAB WinRAR
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Due date
Ransomware use
Known
Vendors
rarlabdtsearch
Products
winrar, dtsearch
Weakness
CWE-35
Vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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