What is CVE-2023-40477?
RARLAB WinRAR Recovery Volume Improper Validation of Array Index Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of RARLAB WinRAR. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the processing of recovery volumes. The issue results from the lack of proper validation of user-supplied data, which can result in a memory access past the end of an allocated buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-21233.
The record classifies CVE-2023-40477 under weakness class CWE-129. Its CVSS v3 base vector states that the flaw requires local access to the host, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 895 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 7.8 — HIGH
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS (FIRST)
- 11.3% probability of exploitation in the next 30 days, higher than 95.8% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 9.7/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2024-05-03, last modified 2025-11-04
Is CVE-2023-40477 being exploited?
Weaponised exploit code for CVE-2023-40477 is publicly available. 3 public proof-of-concept repositories are tracked for this identifier. It currently carries a trending score of 37 in the Threadlinqs vulnerability feed.
- wildptr-io/Winrar-CVE-2023-40477-POC (github)
- winkler-winsen/Scan_WinRAR (github)
- trickest/cve (trickest)
Affected products and versions
- RARLAB: WinRAR
How to fix CVE-2023-40477
No vendor patch reference has been recorded for CVE-2023-40477 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2023-40477
1 tracked threat in the Threadlinqs corpus references CVE-2023-40477, either in the campaign’s CVE list or as an indicator on the campaign record.
- WinRAR 7.23 Fixes Heap Overflow in RAR5 Recovery Volume Processing (CVE-2026-14191) — MEDIUM · 2026-07-02
Sources
Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on .