CVE-2024-35333 in html2xhtml
Summary
by MITRE • 05/29/2024
A stack-buffer-overflow vulnerability exists in the read_charset_decl function of html2xhtml 1.3. This vulnerability occurs due to improper bounds checking when copying data into a fixed-size stack buffer. An attacker can exploit this vulnerability by providing a specially crafted input to the vulnerable function, causing a buffer overflow and potentially leading to arbitrary code execution, denial of service, or data corruption.
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Analysis
by VulDB Data Team • 08/19/2024
The stack buffer overflow vulnerability identified as CVE-2024-35333 resides within the html2xhtml 1.3 software package, specifically within the read_charset_decl function. This function is responsible for processing character set declarations during HTML to XHTML conversion operations, making it a critical component in web content processing pipelines. The vulnerability represents a classic buffer management flaw that occurs when the program fails to properly validate input data lengths against predetermined buffer boundaries, creating an exploitable condition that can be leveraged by malicious actors to compromise system integrity.
The technical flaw manifests as improper bounds checking during data copying operations within the stack buffer allocated for character set declaration processing. When the read_charset_decl function receives input data, it attempts to copy this data into a fixed-size stack buffer without adequate validation of the source data length. This omission allows an attacker to provide input data that exceeds the allocated buffer capacity, resulting in memory corruption that overflows into adjacent stack memory locations. The vulnerability aligns with CWE-121 Stack-based Buffer Overflow, which specifically addresses buffer overflows occurring in stack memory regions due to inadequate boundary checks during data copying operations.
The operational impact of this vulnerability extends beyond simple denial of service conditions to potentially enable arbitrary code execution within the context of the affected application. An attacker exploiting this flaw could manipulate the program flow by overwriting return addresses, saved registers, or other critical stack data structures, thereby gaining control over the execution environment. The vulnerability is particularly concerning in web applications or content processing systems that utilize html2xhtml for automated HTML conversion, as these systems often process untrusted input from external sources, creating multiple attack vectors. Additionally, the vulnerability could lead to data corruption within the processing environment, potentially affecting the integrity of converted documents or system state information.
Mitigation strategies for CVE-2024-35333 should prioritize immediate software updates from the vendor to address the buffer overflow condition in the read_charset_decl function. Organizations should implement input validation measures that enforce strict bounds checking on all data processed by the affected component, including character set declarations and related metadata. Network segmentation and application whitelisting can provide additional defense-in-depth measures by limiting the attack surface and preventing unauthorized access to systems running vulnerable versions of html2xhtml. The vulnerability's exploitation aligns with ATT&CK technique T1203 Exploitation for Client Execution, which involves using vulnerabilities to execute malicious code on target systems. Security teams should also consider implementing runtime monitoring and anomaly detection systems that can identify unusual memory access patterns or buffer overflow attempts during HTML processing operations, providing early warning capabilities for potential exploitation attempts.