Bug 2567083

Summary: CVE-2026-58496 thorvg: thorvg: Information disclosure via undersized font data [fedora-43]
Product: [Fedora] Fedora Reporter: Oleg Sushchenko <osushche>
Component: thorvgAssignee: Benson Muite <benson_muite>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: 43CC: benson_muite
Target Milestone: ---Keywords: Security, SecurityTracking
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Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["d04df067-d4cf-4123-82b4-96f74c238f57"]}
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On:    
Bug Blocks: 2562453    

Description Oleg Sushchenko 2026-11-04 16:21:19 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

Thor Vector Graphics (ThorVG) is a production-ready vector graphics engine. Prior to 1.0.7, the `SFNT/TTF` font loader's `SfntLoader::gen` function in `tvgSfntLoader.cpp` reads `data[0] through data[3]` to identify the font type without first checking that the input buffer contains at least four bytes. Loading an undersized font directly from memory through public APIs such as `tvg::Text::load` causes an out-of-bounds read. Loading through a file path using `mmap` can mask the read because of page alignment; the memory-loading API directly exposes it. Depending on memory layout, a malformed short font may crash the consuming application or disclose adjacent heap memory. This issue is fixed in version 1.0.7.