The nightly fuzz job found a JBIG2 symbol dictionary that decoded for
minutes: each bitmap side may be 65535, and up to 65535 symbols are decoded
pixel by pixel. Vendored hayro-jbig2 0.3.0 with two bounds: at most 2^28
pixels per bitmap (also the page bitmap, halftone grid and grayscale image),
and at most 2^26 symbol pixels per dictionary. The finding now finishes in
about a second. Synthetic regression test (a 65535 x 65535 page and region
behind a small /Width and /Height); the corpus sweep shows 0 regressions.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Brandon Thomas