PT-2026-55366 · Crates.Io · Jxl-Grid

Publicado

2026-07-02

·

Atualizado

2026-07-02

CVSS v3.1

7.3

Alta

VetorAV:L/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:H

Summary

On 32-bit platforms, decoding a crafted image may lead to out-of-bounds writes due to integer overflow in length calculation.

Details & PoC

The test listed below fail under miri with command cargo +nightly miri test --release -p jxl-grid
Or you can use Address Sanitizer, which ignores Rust-specific UB like aliasing but still flags out-of-bounds accesses:
RUSTFLAGS=-Zsanitizer=address cargo +nightly test -Zbuild-std -p jxl-grid --release --target x86 64-unknown-linux-gnu
The following tests should be appended to crates/jxl-grid/src/test/subgrids.rs:
rust
mod miri ub {
  use super::*;

  // `AlignedGrid::with alloc tracker` computes `width * height` unchecked. In release, overflow
  // can create a tiny backing buffer for huge logical dimensions.
  #[test]
  fn aligned grid dimension product overflows() {
    let width = usize::MAX / 2 + 1;
    let mut grid = AlignedGrid::<u8>::with alloc tracker(width, 2, None).unwrap();
    let mut subgrid = grid.as subgrid mut();
    *subgrid.get mut(0, 1) = 1;
    std::hint::black box(grid);
  }
}
This issue can be reachable through decoding a crafted image in two ways:
  1. Huge actual frame A frame such as 65536 x 65536 passes the current frame area limit (2^32 <= 2^40) but overflows usize element count on 32-bit. Rendering then allocates too-small AlignedGrids in modular/VarDCT/filter paths and later writes through mutable subgrids.
  2. Huge canvas plus tiny cropped frame This is the more practical “small payload, huge logical output” case. A bitstream-controlled frame crop can be tiny, but if the canvas/default requested region is huge, composition can allocate an output grid sized to the canvas/ROI at crates/jxl-render/src/blend.rs. That is bitstream frame cropping, not API crop. With a 32-bit target and a full requested image region whose area overflows, this can happen through ordinary render frame().

Impact

On 32-bit platforms this can cause out-of-bounds writes with attacker-controlled data when decoding a crafted JPEG XL image. This could allow arbitrary code execution.

Correção

Integer Overflow

Heap Based Buffer Overflow

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Enumeração de Fraquezas

CWE-190CWE-131CWE-122

Identificadores relacionados

GHSA-5PMV-RX8R-WMV5

Produtos afetados

Jxl-Grid