In the past, security bugs in the Xpdf PDF viewer have endangered Linux systems time and again, and projects that use Xpdf code are also affected.
Security researchers at Secunia have discovered three vulnerabilities in Xpdf 3.02. All three are located in the stream.cc file. The first bug which affects the "DCTStream::readProgressiveDataUnit()" function can lead to memory corruption on indexing an array. The other two bugs, one of which is in the "DCTStream::reset()" function and the other in "CCITTFaxStream::lookChar()", can lead to heap-based buffer overflows. In all three cases, a carefully crafted PDF file is required. If the attacker can trick a victim into opening the file, the attacker may be able to execute arbitrary code.
Secunia discovered the vulnerabilities in Xpdf 3.02 (with xpdf-3.02pl1.patch), however, other versions may also be affected. As many projects, such as Kpdf, Koffice, Cups and Poppler rely on source code by Xpdf, these projects are also affected, as Secunia has proved.
The developers of Xpdf have now released a patch to remove the vulnerabilities. Users who prefer not to build the application from scratch are advised to avoid PDFs from untrusted sources until their distributor releases a new package.
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