WINDANVIL

REDZONE LIVE · FIG. JXL / DUAL DECODE

STOCK FAILS.
PATCH REJECTS.

JXL REDZONE — validation failure → memory-safety finding → verified rejection

COORDINATED DISCLOSURE BOUNDARY. This page replays verified outcomes from a private, sandboxed dual run and visualizes the mechanism conceptually. It does not publish a weaponized input, forge tooling, a rebuildable ASan recipe, or specimen bytes. Remote code execution is not claimed.
SUBJECT libjxl TARGET i386 · ASan IMPACT out-of-bounds read STATUS VERIFIED SANDBOX network=none

DUAL CONTROL

Same private input. Two library builds. One sandboxed Decode path with network=none.

01 / STOCK DECODE

FAIL_ASAN
AddressSanitizer abort on an out-of-bounds READ in the blending path. Process exits non-zero.

02 / PATCHED DECODE

PASS_REJECT
Overflow-safe position validation rejects the input with a clean diagnostic. No ASan.
STOCK OUTCOMEFAIL_ASAN
PATCHED OUTCOMEPASS_REJECT
STOCK SIGNATUREheap-buffer-overflow READ
PATCHED REJECTIONInvalid position…

THE WRAP

How a 32-bit position check passes a value it should have rejected.

FIG. A / ARITHMETIC

STOCK · 32-BIT GUARD

FAIL_ASAN

    PATCHED · OVERFLOW-SAFE

    PASS_REJECT

      THE EVIDENCE

      Real redacted stderr from the verified dual run, anchored to library SHA-256.

      FIG. B / STDERR

      STOCK · ASan REPORT (redacted)

      FAIL_ASAN

      PATCHED · REJECTION

      PASS_REJECT

      TRUST ANCHORS · libjxl.so.0.12.0 SHA-256

      STOCK
      PATCHED

      The two builds differ only in the shared library. Same djxl front-end, same sandboxed input.

      THE PATH

      One entry path, two outcomes.

      FIG. C / CALL PATH
      wrap accepted (stock) OOB READ (stock) reject fires (patched) never reached (patched)

      DISCLOSURE / WHAT THIS IS NOT

      private coordinated disclosure · captured

      WindAnvil REDZONE Live is a public instrument for a private finding. Upstream maintainers were notified. A CVE identifier is not asserted on this page.

      Explicitly not claimed and not published here:

      • remote code execution
      • public weaponized reproducer

      No private specimen file, forge hook, or rebuildable ASan recipe is served from this origin. The wrap board uses conceptual arithmetic that does not reconstruct an input file.