Search: CVE-2026-33636

An out-of-bounds read and write vulnerability exists in libpng versions 1.6.36 through 1.6.55 in the ARM/AArch64 Neon-optimized palette expansion code. This occurs when expanding 8-bit paletted rows to RGB or RGBA, where the Neon loop processes a final partial chunk without verifying input pixel boundaries, causing pointer underflow and memory corruption. The issue can be triggered by decoding attacker-controlled PNG files if Neon is enabled. Version 1.6.56 addresses this vulnerability.