ModSecurity < 2.9.7 WAF Bypass via '\0' in FILES_TMP_CONTENT
CVE-2023-24021 Published on January 20, 2023
Incorrect handling of '\0' bytes in file uploads in ModSecurity before 2.9.7 may allow for Web Application Firewall bypasses and buffer over-reads on the Web Application Firewall when executing rules that read the FILES_TMP_CONTENT collection.
Vulnerability Analysis
CVE-2023-24021 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, a high impact on integrity, and no impact on availability.
Weakness Type
Improper Null Termination
The software does not terminate or incorrectly terminates a string or array with a null character or equivalent terminator. Null termination errors frequently occur in two different ways. An off-by-one error could cause a null to be written out of bounds, leading to an overflow. Or, a program could use a strncpy() function call incorrectly, which prevents a null terminator from being added at all. Other scenarios are possible.
Products Associated with CVE-2023-24021
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Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.