CVE-2023-40477: WinRAR's Patch for Remote Code Execution Vulnerability
WinRAR patched CVE-2023-40477, an improper array index validation flaw that can allow arbitrary code execution when a user opens a compromised archive. WinRAR versions before 6.23 are affected; updating to 6.23 fixes the vulnerability.
Summary written with AI from this article, and checked against it.
At a glanceCVE-2023-40477
CVE-2023-40477 has a CVSS 3.0 base score of 7.8 (High) from Trendmicro. It is fixed in WinRAR 6.23. Debian bookworm/non-free fixed it in libclamunrar 1.3.1-1~deb12u1.
| Severity | 7.8 High (CVSS 3.0, Trendmicro) |
|---|---|
| Fixed in | WinRAR 6.23 |
| Affected | WinRAR before 6.23 |
| Exploited | Not in CISA's Known Exploited Vulnerabilities catalog |
| EPSS | 11% chance of exploitation in the next 30 days (FIRST, October 27, 2026) |
| Public exploit | 2 GitHub repositories name it: proofs of concept, scanners, detections. Unverified: some are fake or malicious. |
| Vector | CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| Weakness | CWE-129 Improper Validation of Array Index |
| Ubuntu | Not tracked yet |
| Debian | bookworm/non-free libclamunrar: Fixed (1.3.1-1~deb12u1) · trixie/non-free libclamunrar: Fixed (1.3.1-1) · forky/non-free, sid/non-free libclamunrar: Fixed (1.4.4-1) · bookworm/non-free rar: Fixed (2:7.01-1~deb12u1) · trixie/non-free rar: Fixed (2:7.11-1) · forky/non-free, sid/non-free rar: Fixed (2:7.23-1) |
| Red Hat | Not tracked yet |
Is there a public exploit for CVE-2023-40477?
Public code exists as of October 28, 2026: 2 public GitHub repositories name it (proofs of concept, scanners and detections). It is not in CISA's Known Exploited Vulnerabilities catalog. None of it is verified: some such repositories are fake or carry malware, so read the code before running it, and only against systems you own. FIRST's EPSS puts the chance of exploitation in the next 30 days at 11%, higher than 95.9% of scored CVEs.
In the realm of cybersecurity, the timely identification and patching of software vulnerabilities is critical. Recently, a significant flaw was discovered in the widely-used file archiving software, WinRAR. Identified as CVE-2023-40477, this remote code execution vulnerability has now been addressed with an essential patch.
Overview of CVE-2023-40477
CVE-2023-40477 pertains to a remote code execution vulnerability within WinRAR. Remote Code Execution, or RCE, allows an attacker to execute arbitrary codes on a victim's machine without their knowledge. In the context of WinRAR, this could potentially let attackers introduce malicious payloads into a system when a user opens a compromised archive.
WinRAR's Response
Upon becoming aware of the vulnerability, WinRAR's development team acted swiftly. They released a patch to address the flaw, urging users to update their software to the latest version immediately. This proactive approach ensures the safety of WinRAR's vast user base, preventing potential breaches and data compromises.
Importance of Regular Updates
Software vulnerabilities are inevitable in the rapidly evolving world of technology. However, users can safeguard themselves by maintaining a routine of regular software updates. In the case of WinRAR, updating to the latest version mitigates the risk posed by CVE-2023-40477.
Conclusion
The discovery and prompt patching of CVE-2023-40477 in WinRAR underscore the ongoing challenges in cybersecurity. As vulnerabilities surface, developers and users alike must remain vigilant. By ensuring that software is consistently updated and monitored for flaws, users can effectively shield their systems from potential threats.
Source
- CVE recordCVE-2023-40477 in the National Vulnerability Database · nvd.nist.gov
About the author
Vishal · Software & security engineerVishal writes Trickyworld's tutorials and interview-preparation guides on programming, databases, cyber security and AI. Vishal has been shipping production software long enough to have firm opinions about Python, PHP, Node.js, and JavaScript, and to have been wrong about each of them at least once. The work has run the whole stack: Drupal and Laravel applications, React front ends, MySQL and MongoDB underneath, Redis and Memcached for the things that had to be fast, Apache Solr for the things that had to be findable. That last part turned out to matter more than anyone expected. Tune a Solr index for a season, then watch a language model confidently retrieve the wrong document, and you recognise an old problem wearing new clothes. Most of what is hard about AI systems is not the model. It is retrieval, caching, latency budgets, and deciding what the system does when the answer comes back wrong — which is work he has been doing since well before anyone called it AI engineering. He plays a lot of games, which is less a hobby disclosure than an admission of where a good share of his engineering instinct came from. Real-time systems with a frame budget. State that has to stay coherent while a player does something no designer anticipated. The permanent question of what happens when the frame cannot finish in time. Those habits carry over more directly than they have any right to. He has written several books on programming, all built on the same conviction: most technical writing is unclear because the author never decided what to leave out. More from Vishal → · Editorial policy
