Out-of-bounds Read in Thorvg
CVE-2026-58496
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.
Vulnerability class: Buffer Overflow
Published .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Thorvg — versions < 1.0.7
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-58496?
- CVE-2026-58496 is a medium-severity vulnerability in Thorvg, classified under Out-of-bounds Read. CVSS score: 4.3/10. Published 2026-10-27.
- How severe is CVE-2026-58496?
- Medium severity. CVSS v3 base score is 4.3 out of 10.