CVE-2018-11575 in ngiflib
Summary
by MITRE
ngiflib.c in MiniUPnP ngiflib 0.4 has a stack-based buffer overflow in DecodeGifImg.
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Analysis
by VulDB Data Team • 02/10/2020
The vulnerability identified as CVE-2018-11575 resides within the ngiflib.c component of MiniUPnP ngiflib version 0.4, specifically manifesting as a stack-based buffer overflow within the DecodeGifImg function. This flaw represents a critical security weakness that can be exploited to compromise system integrity and potentially execute arbitrary code. The vulnerability stems from inadequate input validation and memory management practices during the processing of GIF image files, making it particularly dangerous in environments where untrusted image data might be processed.
The technical nature of this vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows attackers to overwrite adjacent memory locations on the stack. When the DecodeGifImg function processes malformed GIF image data, it fails to properly validate the size of image data before copying it into fixed-size buffers allocated on the stack. This allows an attacker to craft specially malformed GIF files that, when processed by the vulnerable library, trigger memory corruption that can be leveraged for code execution or denial of service attacks.
The operational impact of this vulnerability extends beyond simple system crashes, as it can enable remote code execution when the affected library is used in network services or applications that process user-uploaded GIF images. Attackers can exploit this weakness by submitting maliciously crafted GIF files to applications using the ngiflib library, potentially leading to complete system compromise. The vulnerability affects any system running MiniUPnP ngiflib 0.4 or earlier versions, particularly those that handle GIF image processing in web applications, network devices, or embedded systems that utilize the library for UPnP functionality.
Security professionals should consider this vulnerability in the context of the ATT&CK framework, specifically under the T1059 technique for command and control through remote code execution. The vulnerability can be exploited as part of a broader attack chain where initial access is gained through image processing components, followed by privilege escalation and lateral movement within the compromised network. Mitigation strategies should include immediate patching of affected systems, implementing input validation controls, and deploying network segmentation to limit the potential impact of exploitation. Organizations should also consider implementing application whitelisting policies to prevent execution of unauthorized code and monitor for suspicious network activity that might indicate exploitation attempts.
The remediation approach for CVE-2018-11575 requires upgrading to a patched version of MiniUPnP ngiflib where the DecodeGifImg function properly validates input sizes and implements appropriate buffer management techniques. Security teams should also conduct comprehensive vulnerability assessments to identify all systems utilizing the affected library and ensure proper input sanitization measures are in place. Additionally, implementing proper memory protection mechanisms such as stack canaries and address space layout randomization can provide additional defense-in-depth measures against exploitation attempts targeting this class of buffer overflow vulnerability.