CVE-2017-14929 in Poppler
Summary
by MITRE
In Poppler 0.59.0, memory corruption occurs in a call to Object::dictLookup() in Object.h after a repeating series of Gfx::display, Gfx::go, Gfx::execOp, Gfx::opFill, Gfx::doPatternFill, Gfx::doTilingPatternFill and Gfx::drawForm calls (aka a Gfx.cc infinite loop), a different vulnerability than CVE-2017-14519.
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Analysis
by VulDB Data Team • 12/30/2022
The vulnerability described in CVE-2017-14929 represents a critical memory corruption issue within the Poppler PDF rendering library version 0.59.0. This flaw manifests through a specific sequence of graphical operations that create an infinite loop within the Gfx.cc component, leading to unpredictable memory behavior and potential system compromise. The vulnerability is particularly concerning because it operates at the core rendering level of PDF document processing, where memory management and execution flow are paramount to system stability.
The technical root cause of this vulnerability lies in the improper handling of dictionary lookups within the Object::dictLookup() method in Object.h. When a specific sequence of graphics operations is executed in a repetitive pattern - namely Gfx::display, Gfx::go, Gfx::execOp, Gfx::opFill, Gfx::doPatternFill, Gfx::doTilingPatternFill, and Gfx::drawForm - the system enters an infinite loop that exhausts memory resources and corrupts heap memory structures. This sequence creates a condition where the object reference counting mechanism fails to properly manage memory allocation and deallocation, resulting in memory corruption that can be exploited by malicious actors.
From an operational perspective, this vulnerability poses significant risks to any system that processes PDF documents through the Poppler library. The infinite loop behavior can cause applications to crash, consume excessive system resources, or potentially allow remote code execution depending on the specific exploitation vector. The vulnerability's classification as a memory corruption issue aligns with CWE-121, which describes heap-based buffer overflow conditions, and its behavior demonstrates characteristics consistent with CWE-787, indicating an out-of-bounds write operation. The attack surface is particularly wide given that Poppler is widely used across various operating systems and applications for PDF rendering.
The impact of this vulnerability extends beyond simple application instability to potential security breaches that could compromise entire systems. When exploited, the memory corruption can lead to arbitrary code execution, allowing attackers to gain unauthorized access to systems processing vulnerable PDF documents. The vulnerability's relationship to the ATT&CK framework demonstrates its potential for privilege escalation and lateral movement within compromised environments, as the memory corruption can be leveraged to manipulate program execution flow and potentially elevate privileges. Organizations relying on Poppler for PDF processing must consider the implications of this vulnerability in their security posture and implement appropriate mitigation strategies.
Mitigation efforts should focus on immediate patching of Poppler library versions to address the memory corruption issue, while also implementing runtime protections such as address space layout randomization and stack canaries to reduce exploitability. Network-based protections including PDF content filtering and sandboxing mechanisms can provide additional layers of defense against exploitation attempts. Regular security assessments and vulnerability scanning should be implemented to identify systems running vulnerable versions of Poppler, while application developers should consider implementing input validation and memory safety checks to prevent exploitation of similar vulnerabilities in their own code. The vulnerability underscores the importance of proper memory management in graphics rendering libraries and highlights the need for comprehensive security testing of core system components that handle untrusted data input.