ZeroHour
DashboardNewsCVEsExploitsIncidentsAIBriefAnalyticsEntitiesWatchlistIOCsAsk the feedSourcesFeeds & APIKiosk mode
CyberScooppublished ()ingested @CyberScoopNews1

Cybercriminals and nation-state groups are exploiting a six

criticalThreat actor exploited in the wildimportance 60CVE-2025-8088CVE-2023-38831
Read the original
Tagscve-2025-8088cve-2023-38831threat-actor

Vulnerabilities mentionedAll →

CVEVulnerabilityCVSSEPSSFlagsAffectedExposurePublished
CVE-2023-38831
Code Execution in RARLAB WinRAR via Crafted ZIP File/Folder Name Confusion

RARLAB WinRAR before 6.23 mishandles ZIP archives that contain a benign file (such as a JPG) alongside a folder with the same name, causing the folder's contents - which can include malicious executable files - to be processed when the user merely attempts to view the benign file. By sending a crafted ZIP archive, an attacker gains arbitrary code execution on the victim's machine with the user's privileges. Because the flaw is local (AV:L) and requires user interaction, risk is limited to Windows systems running an unpatched copy of WinRAR, while machines without the tool are unaffected. The bug was actively exploited in the wild from April through October 2023, including by government-backed actors (APT28), SideCopy attacks on Indian government entities, ransomware operations, and trading-account theft campaigns, and it was added to CISA's Known Exploited Vulnerabilities catalog on 2023-08-24.

Do: Upgrade all Windows systems running WinRAR to version 6.23 or later, which fixes this flaw; if patching is not immediately possible, treat ZIP files from untrusted sources with caution and check archives for duplicate file/folder names before opening. Given KEV listing with known ransomware use and public proof-of-concept exploits, hunt for compromise by reviewing whether unexpected executables or scripts ran when ZIP archives were opened, and apply vendor mitigations per CISA's required action or discontinue use if mitigations are unavailable.

7.898% KEV ransomware PoC ×4
  • RARLAB WinRAR before 6.23
masshundreds of millions of users/installations worldwide (WinRAR is one of the most widely installed Windows archive utilities)
CVE-2025-8088
WinRAR Path Traversal (CVE-2025-8088) Enables Arbitrary Code Execution

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.

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.

8.495% KEV ransomware
  • RARLAB WinRAR
  • dtsearch
masshundreds of millions of Windows users/devices (est.; RARLAB has historically claimed user counts in the hundreds of millions)
Full article699 words · extracted from cyberscoop.com · click to collapse
Skip to main content

Get our latest cybersecurity news first on Google.

Click here!

Nation-state groups are consistently exploiting the defect to target victims in military, government and technology for espionage.

Listen to this article

0:00

Learn more.

Binary code depicted in waves.
Binary code depicted in waves. (iStock/Getty Images)

Google Threat Intelligence Group warned that a diverse and growing collection of attackers, including nation-state groups and financially motivated cybercriminals, are exploiting a path-traversal vulnerability affecting WinRAR that was disclosed and patched six months ago.

The high-severity vulnerability — CVE-2025-8088 — was exploited in the wild almost two weeks before RARLAB, the vendor behind the file archiver tool, addressed the vulnerability in a software update in late July. 

Active exploitation of the vulnerability has consistently extended to more threat groups during the past six months and remains ongoing. Google threat hunters have attributed attacks to at least three financially motivated attackers, four Russia state-sponsored groups and one attacker based in China. 

“Government-backed threat actors linked to Russia and China as well as financially motivated threat actors continue to exploit this n-day across disparate operations,” Google said in a threat intelligence report Tuesday. Researchers did not say how many attacks are linked to the vulnerability but described the activity as widespread.

Nation-state groups are consistently exploiting the defect to target victims in military, government and technology for espionage, researchers said. Groups backed by Russia are targeting Ukrainian military and government entities while the China-based attacker’s targets remain unknown. 

Cybercriminals are swarming to exploit the vulnerability, too. Google traced campaigns back to groups that previously targeted victims in Indonesia, Latin America and Brazil. Cybercrime groups exploited the vulnerability in December and January to deploy malware, including remote access trojans and infostealers.

Google published a timeline of observed exploitation depicting a broad set of attackers involved through October, but the majority of malicious activity since late 2025 is attributed to cybercriminals. 

Attacks share a common method of exploitation, which was rapidly adopted by a range of threat groups. 

“We are seeing both government-backed groups and financially motivated actors use the same exploitation method to achieve successful execution on target devices,” GTIG said in an email. “This mechanism of crafting a malicious RAR archive makes it more difficult for victims to determine they’ve been impacted, as they are shown a benign decoy file while in the background it silently drops a malicious payload into a critical system location such as Windows Startup folder.”

The malware requires no user interaction and because there are no obvious indicators of compromise, the malicious activity is very difficult to spot, researchers said.

Attackers of various objectives are flocking to the vulnerability, reminiscent of widespread exploitation of a previous WinRAR defect — CVE-2023-38831 — that Google’s Threat Analysis Group warned about in October 2023. 

“The barrier to entry for threat actors to abuse WinRAR vulnerabilities is low, as there are public ready-to-use tools to quickly craft and test malicious archives,” researchers said. Google urged organizations to install security updates for WinRAR and published indicators of compromise to help defenders hunt for malicious activity on their systems.

Latest Podcasts

Text extracted automatically; images, tables and formatting may be missing. Original: https://cyberscoop.com/winrar-defect-active-exploits-google-threat-intel/