Overview
The vulnerability CVE-2024-53924 is a serious security flaw in Pycel, a Python library widely used for its powerful spreadsheet manipulation capabilities. The vulnerability, which is present in versions up to and including 1.0b30, allows potential attackers to execute arbitrary code on a targeted system via a maliciously crafted formula in a spreadsheet cell. Given the widespread use of Pycel in various applications and services, this vulnerability has a broad impact, potentially allowing unauthorized access to sensitive information or even compromising entire systems.
Vulnerability Summary
CVE ID: CVE-2024-53924
Severity: Critical (CVSS 9.8)
Attack Vector: Network
Privileges Required: None
User Interaction: Required
Impact: System compromise and potential data leakage
Affected Products
No phone number, email, or personal info required.
Product | Affected Versions
Pycel | Up to and including 1.0b30
How the Exploit Works
The vulnerability stems from Pycel’s handling of spreadsheet formulas. When an untrusted spreadsheet is processed by Pycel, a maliciously crafted cell formula, such as one beginning with the IF function, can trigger arbitrary code execution. The arbitrary code is executed when the IF condition is met. By exploiting this flaw, an attacker could execute any command on the host system.
Conceptual Example Code
As a conceptual example, consider a spreadsheet containing a cell with the following formula:
=IF(A1=200, eval("__import__('os').system('rm -rf /')"), "")If Pycel processes this spreadsheet and the value of cell A1 is 200, it would trigger the eval function, importing the os module and executing the ‘rm -rf /’ command, which deletes all files in the root directory of the Unix-based host system.
Impact of the Exploit
A successful exploitation of this vulnerability could lead to complete system compromise or potential data leakage. An attacker could manipulate, exfiltrate, or delete data. In the worst-case scenario, the attacker could gain complete control over the system, depending on the system’s privileges.
Mitigation Guidance
Users of Pycel are strongly advised to apply the vendor’s patch as soon as possible. In the interim, a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can be used to mitigate the risk, but these are temporary measures and not a substitute for the vendor’s patch.