Buffer overflow in Thorvg

CVE-2026-123367

Thor Vector Graphics (ThorVG) is a production-ready vector graphics engine. Prior to 1.1.2, the bundled jpgd JPEG decoder accepts duplicate component selectors in an SOS scan header, causing each duplicate to increase m_blocks_per_mcu without checking the buffers sized from the frame components. A crafted grayscale JPEG can repeat its component in the SOS header, causing decode paths in src/loaders/jpg/tvgJpgd.cpp to write beyond heap buffers sized for one component. The issue is reachable through direct JPEG decoding and through JPEG images embedded in Lottie content, and confirmed impact is memory corruption followed by a process crash. This issue is fixed in version 1.1.2.

Vulnerability class: Buffer Overflow

Published .

CVSS v3 metric

CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:H.

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

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-123367?
CVE-2026-123367 is a high-severity vulnerability in Thorvg, classified under Out-of-bounds Write. CVSS score: 7.4/10. Published 2026-11-09.
How severe is CVE-2026-123367?
High severity. CVSS v3 base score is 7.4 out of 10.