CVE-2023-38831
RARLAB — RARLAB WinRAR Code Execution Vulnerability
RARLAB · CWE-345 | CWE-351 · in CISA KEV since 2023-08-24
EVRS 91 of 100 Immediate
Patch Immediately
Rank 115 of 2,960 tracked
Why it scores 91
Evidence available: 6 of 7 signalsListed in the CISA KEV catalog, and associated with known ransomware campaigns.
- CISA KEVApplied
- RansomwareApplied
- Vendor exploitationDid not apply
- EPSSApplied
- Microsoft Exploitability IndexNot applicable
- Pre-patch disclosureNo data
- KEV recencyDid not apply
- CVSSApplied
The band answers “how soon”, not “how bad”. No data for: Pre-patch disclosure. Why some signals show no data
Fix
Patch or fixed version identifiedCISA required action
- www.win-rar.com/…/singlenewsview.html?&L=0&tx_ttnews%5Btt_news%5D=232&cHash=c5bf79590657e32554c6683296a8e8aa
- nvd.nist.gov/…/CVE-2023-38831
Fixed in
winrar: update to 6.23 or later
Affected versions
- winrar
< 6.23
Remediation
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Fixed versions from NVD.
Evidence
Each value with its source| Measure | Value | Source |
|---|---|---|
| CVSS base scoreHow severe the flaw is in itself. It does not say how likely an attack is. | 7.8 | NVD |
| FIRST EPSSFIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. | 0.998 (99.96th pctl) | FIRST EPSS |
| Actively exploitedWhether a source of record has confirmed attacks using it in the wild. | Confirmed | CISA KEV |
| Ransomware campaign useWhether CISA has seen ransomware operators use it. | Known | CISA KEV |
| CISA remediation deadlineThe date US federal agencies must have fixed or mitigated it. | 2023-09-14 · KEV since 2023 · listed over a year | CISA KEV |
| Public exploit moduleA module existing is not the same as active exploitation. | Public module exists | Metasploit |
| EUVD cross-referenceENISA's record: CVSS 7.8 (v3.1), assigned by mitre. | Listed | ENISA EUVD |
Description
NVDRARLAB 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.
What CISA says to do
- www.win-rar.com/…/singlenewsview.html?&L=0&tx_ttnews%5Btt_news%5D=232&cHash=c5bf79590657e32554c6683296a8e8aa
- nvd.nist.gov/…/CVE-2023-38831
Public module
Metasploit lists a public excellent-rank module for this CVE: WinRAR CVE-2023-38831 Exploit (windows/fileformat/winrar_cve_2023_38831). A module existing is not the same as active exploitation; see metasploit.com.