{"id":"CVE-2023-38831","kind":"vulnerability","aliases":["CVE-2023-38831"],"related":[],"title":"RARLAB WinRAR before 6.23 allows attackers to execute arbitrary code when a user attempts to view a benign file…","description":"RARLAB WinRAR before 6.23 allows attackers to execute arbitrary code when a user attempts to view a benign file within a ZIP archive. The issue occurs because a ZIP archive may include a benign file (such as an ordinary .JPG file) and also a folder that has the same name as the benign file, and the contents of the folder (which may include executable content) are processed during an attempt to access only the benign file. This was exploited in the wild in April through October 2023.","summary":"WinRAR, a Windows archive tool, has a flaw that lets an attacker run code when a user opens a harmless-looking file inside a ZIP archive. CISA lists it as actively exploited in the wild.","severity":"high","cvss":7.8,"epss":null,"exploited":true,"exploited_at":"2023-08-24T00:00:00+00:00","products":[{"name":"rarlab winrar","fixed":["6.23"],"affected":"< 6.23","ecosystem":"vendor"},{"name":"RARLAB WinRAR","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["end-users","exploited","package","ransomware","windows","winrar"],"not_affected_if":["not-installed"],"how_to_check":"Check the installed WinRAR version (Help > About WinRAR) against the vendor's fixed release.","fix":"Update WinRAR to the vendor's patched release; if no mitigation is available, stop using WinRAR per CISA's required action.","status":"open","published_at":"2023-08-23T17:15:43+00:00","first_seen_at":"2026-10-23T19:11:51+00:00","triaged_at":"2026-10-23T21:04:47+00:00","updated_at":"2026-10-24T00:09:51+00:00","category":"package","confidence":0.8,"triage":{"at":"2026-10-23T21:04:47Z","model":"claude-haiku-5-5","output":{"fix":"Update WinRAR to the vendor's patched release; if no mitigation is available, stop using WinRAR per CISA's required action.","reach":"internet","impact":"high","summary":"WinRAR, a Windows archive tool, has a flaw that lets an attacker run code when a user opens a harmless-looking file inside a ZIP archive. CISA lists it as actively exploited in the wild.","category":"package","who_cares":["windows","winrar","end-users"],"confidence":0.8,"needs_auth":"no","worst_case":"Attacker runs arbitrary code on the user's Windows machine after opening an archive.","analyst_note":"Confirm the patched WinRAR version and the vendor mitigation from rarlab.com or the CISA KEV entry; sources here give no affected or fixed versions.","how_to_check":"Check the installed WinRAR version (Help > About WinRAR) against the vendor's fixed release.\nunknown","needs_analyst":true,"not_affected_if":["not-installed"],"user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000473,"input_tokens":2821,"output_tokens":381,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2023':21A,24A '-38831':22A,25A '2023':160C '6.23':4A,77C 'access':145C 'activ':69B 'allow':5A,78C 'also':116C 'april':157C 'arbitrari':9A,82C 'archiv':41B,64B,96C,103C 'attack':6A,49B,79C 'attempt':14A,87C,143C 'benign':18A,91C,107C,126C,148C 'cisa':65B 'code':10A,51B,83C 'content':130C,138C 'cve':20A,23A 'end':31B 'end-us':30B 'execut':8A,81C,137C 'exploit':33B,70B,152C 'file':19A,60B,92C,108C,114C,127C,149C 'flaw':45B 'folder':118C,133C 'harmless':58B 'harmless-look':57B 'includ':105C,136C 'insid':61B 'issu':98C 'jpg':113C 'let':47B 'list':66B 'look':59B 'may':104C,135C 'name':123C 'occur':99C 'octob':159C 'open':55B 'ordinari':112C 'packag':34B 'process':140C 'ransomwar':35B 'rarlab':1A,26A,28A,74C 'run':50B 'tool':42B 'user':13A,32B,54B,86C 'view':16A,89C 'wild':73B,155C 'window':36B,40B 'winrar':2A,27A,29A,37B,38B,75C 'within':93C 'zip':63B,95C,102C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2023-08-23T17:15:43+00:00","kev":{"dateAdded":"2023-08-24","dueDate":"2023-09-14","requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","knownRansomwareCampaignUse":"Known"},"cvss_vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cvss_by":"nvd@nist.gov","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2023-38831","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-38831","severity":null,"published_at":"2023-08-24T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:51+00:00","fetched_at":"2026-10-26T21:20:25+00:00","note":null},{"source":"nvd","external_id":"CVE-2023-38831","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-38831","severity":null,"published_at":"2023-08-23T17:15:43+00:00","modified_at":"2026-08-05T05:16:38+00:00","first_seen_at":"2026-10-23T22:29:04+00:00","fetched_at":"2026-10-23T22:29:04+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}