CVE-2012-1173 in iOS
Summary
by MITRE
Multiple integer overflows in tiff_getimage.c in LibTIFF 3.9.4 allow remote attackers to execute arbitrary code via a crafted tile size in a TIFF file, which is not properly handled by the (1) gtTileSeparate or (2) gtStripSeparate function, leading to a heap-based buffer overflow.
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Analysis
by VulDB Data Team • 04/13/2021
The vulnerability identified as CVE-2012-1173 represents a critical security flaw within the LibTIFF library version 3.9.4, specifically affecting the tiff_getimage.c component. This issue stems from improper handling of tile size parameters within TIFF image files, creating conditions where remote attackers can manipulate image data to trigger memory corruption. The vulnerability manifests through two distinct code paths involving the gtTileSeparate and gtStripSeparate functions, both of which fail to adequately validate or sanitize tile size values before processing. The flaw operates at the intersection of memory management and input validation, creating a pathway for attackers to craft malicious TIFF files that exploit integer overflow conditions during image decoding operations.
The technical implementation of this vulnerability involves integer overflow conditions that occur when the TIFF library processes tile dimensions within image files. When a crafted TIFF file contains oversized or malformed tile size parameters, the library's internal calculations exceed the maximum representable values for integer data types, resulting in unexpected behavior. The heap-based buffer overflow that follows from these integer overflows occurs because the library allocates memory based on the corrupted tile size values, creating insufficient buffer space for the actual image data processing. This memory corruption scenario directly violates fundamental security principles of input validation and memory safety, as demonstrated by the CWE-190 classification for integer overflow conditions. The vulnerability's remote exploitation capability means that attackers can deliver malicious TIFF files through network-based delivery mechanisms without requiring local access to the target system.
The operational impact of CVE-2012-1173 extends beyond simple code execution, as it represents a serious threat to systems processing TIFF image data. Applications that utilize LibTIFF for image handling, including web servers, image processing applications, and document management systems, become vulnerable to arbitrary code execution when processing untrusted TIFF files. The vulnerability's exploitation can lead to complete system compromise, data theft, or service disruption, particularly in environments where automated image processing occurs. Security professionals should note that this vulnerability aligns with ATT&CK technique T1203 for exploitation of remote services and T1059 for command execution through compromised applications. The impact is particularly severe in server environments where TIFF files are processed automatically, as attackers can leverage this vulnerability to establish persistent access or execute malicious payloads without user interaction.
Mitigation strategies for this vulnerability require immediate patching of affected LibTIFF installations to versions that address the integer overflow conditions in the tiff_getimage.c component. Organizations should implement input validation measures that restrict tile size parameters to reasonable bounds, particularly when processing untrusted image data. Network segmentation and application whitelisting can help limit the attack surface by preventing unauthorized applications from processing potentially malicious TIFF files. Security monitoring should focus on detecting unusual image processing activities or file size variations that might indicate exploitation attempts. The vulnerability also underscores the importance of maintaining updated third-party libraries and implementing comprehensive software supply chain security measures. Regular security assessments and vulnerability scanning should include checks for outdated LibTIFF versions to prevent similar issues from remaining unaddressed in production environments.