WinRAR ACE Archive Path Traversal Arbitrary File Write
CVE-2018-20250 is a path traversal vulnerability in WinRAR prior to and including version 5.61 in its handling of ACE archives via UNACEV2.dll. By crafting the ACE archive filename field with specific path patterns, an attacker can cause WinRAR to ignore the user-selected extraction directory and treat the embedded filename as an absolute or traversal-controlled path. This results in arbitrary file write outside the intended extraction folder during archive extraction. Public reporting and observed exploitation show attackers using this behavior to place payloads into sensitive locations such as the Windows Startup folder or Microsoft Word add-in directories, turning the file write primitive into code execution when the written file is later invoked by normal system or application behavior.
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Impact, mitigation & remediation
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Impact
What an attacker gets, and what they’ve been doing with it.
Mitigation
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Remediation
Patch, then assume compromise.
Exploits
1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (2 hidden).
This repository provides a Python exploit script (exp.py) that generates a malicious RAR archive designed to exploit a path traversal/code execution vulnerability in WinRAR (as described in Check Point's research). The script takes an attacker-supplied executable (e.g., calc.exe) and crafts a RAR file (test.rar) that, when extracted by a victim using a vulnerable version of WinRAR, will drop the executable into the victim's Windows Startup folder (C:\C:C:../AppData/Roaming/Microsoft/Windows/Start Menu/Programs/Startup/hi.exe). This ensures the payload will execute on the next system reboot. The archive also contains decoy files (hello.txt, world.txt) to appear innocuous. The exploit requires the attacker to provide the payload and specify the target path. The repository consists of the main exploit script (exp.py), two decoy text files, and a README.md with usage instructions and background. No network endpoints are involved; the attack vector is local, relying on user interaction with the malicious archive.
Affected products & vendors
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Recent activity
15 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
An older WinRAR vulnerability referenced as an example of long-tail exploitation in targeted attacks years after disclosure.
An older WinRAR vulnerability cited as an example of long-term exploitation in targeted attacks years after disclosure.
A previously exploited archive path traversal vulnerability referenced as an earlier example of Gamaredon using similar WinRAR-based path traversal tradecraft.
난수 또는 nonce 생성 오류와 관련된 과거 취약점의 예시로 언급된다.
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Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
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Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.