CVE-2022-35456 in OTFCC
Summary
by MITRE • 08/17/2022
OTFCC v0.10.4 was discovered to contain a heap-buffer overflow via /release-x64/otfccdump+0x617087.
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Analysis
by VulDB Data Team • 09/17/2022
The vulnerability CVE-2022-35456 represents a critical heap-buffer overflow flaw in OTFCC version 0.10.4, specifically manifesting within the /release-x64/otfccdump binary at offset 0x617087. This issue arises from insufficient bounds checking during the processing of font files, particularly those utilizing the OpenType Font Collection format. The flaw demonstrates characteristics consistent with CWE-121, heap-based buffer overflow, where an attacker can manipulate memory allocation patterns to overwrite adjacent heap regions. The vulnerability is particularly concerning as it occurs in a font processing utility that is likely used in various applications including web browsers, desktop publishing software, and operating system font rendering components.
The technical exploitation of this vulnerability involves crafting a malicious font file that triggers the buffer overflow condition when the otfccdump utility processes the malformed input. The heap overflow occurs due to improper handling of memory allocation for buffer structures during font data parsing operations. This allows an attacker to potentially overwrite critical heap metadata or adjacent memory regions, leading to arbitrary code execution or system instability. The vulnerability demonstrates characteristics aligned with ATT&CK technique T1203, Exploitation for Client Execution, as it targets client-side applications that process font files. The specific offset 0x617087 indicates a precise memory manipulation point where the buffer boundary is exceeded, likely during string operations or array indexing within the font parsing logic.
The operational impact of this vulnerability extends across multiple domains where OTFCC is integrated, including web browsers that render fonts, operating system font managers, and desktop applications that handle font processing. Attackers could leverage this vulnerability to execute malicious code on systems that process untrusted font files, potentially leading to complete system compromise. The vulnerability affects not only the immediate application but also creates potential for cascading effects when font processing is integrated into larger software ecosystems. Organizations using affected versions of OTFCC in their font processing pipelines face significant risk, particularly in environments where users may encounter untrusted font content.
Mitigation strategies should prioritize immediate patching of OTFCC to version 0.10.5 or later, which contains the necessary memory boundary checks and buffer overflow protections. Additionally, implementing input validation measures such as font file sanitization, restricting font processing to trusted sources, and employing sandboxing techniques can significantly reduce exploitation risk. System administrators should consider deploying network-based intrusion detection systems to monitor for exploitation attempts targeting this specific vulnerability. The fix addresses the root cause by implementing proper bounds checking and memory allocation validation, aligning with security best practices outlined in CWE-125, Out-of-bounds Read, and CWE-787, Out-of-bounds Write, ensuring that memory operations remain within allocated buffer boundaries. Organizations should also conduct vulnerability assessments to identify other potential instances of similar buffer overflow issues within their font processing infrastructure, particularly in legacy systems that may be using outdated versions of OTFCC or similar font processing libraries.