SQUISH is pre-1.0 and does not yet maintain parallel release branches. Security fixes are made against main; please use the latest commit.

Please do not open a public GitHub issue for security vulnerabilities.

Instead, report it privately by emailing paige@paigejulianne.com with:

• A description of the vulnerability and its potential impact
• Steps to reproduce (a minimal input file or code snippet is ideal)
• The commit hash or version you tested against

You should receive an acknowledgment within a few days. Once a fix is available, a new release will be cut and the reporter credited (unless they prefer to remain anonymous).

Relevant vulnerability classes for this project include:

• Memory-safety issues in squish.c/squish.h (buffer overflows, out-of-bounds reads/writes, use-after-free) reachable via squish_decompress_alloc/squish_compress_alloc on attacker-controlled input
• Integer overflows in size/length handling that could lead to under-allocation
• Decompression bombs or other resource-exhaustion issues distinct from the documented squish_compress_bound guarantees
• Checksum/integrity bypass allowing corrupted data to decompress as valid

Since SQUISH decompresses untrusted input in many use cases, crashes or memory-safety bugs triggered by malformed compressed streams are treated as security issues, not just correctness bugs.

Callers feeding untrusted streams to the *_alloc/file helpers should know:

• The output allocation is controlled by the archive header, up to the format limit of 4 GiB − 16 bytes per member. Check squish_content_size() first and refuse sizes your application cannot afford.
• Model state costs ~150 MB per active block — times the thread count when nthreads splits a member across cores.
• Context mixing has no compression-ratio ceiling, so a tiny valid stream legitimately expanding to gigabytes (e.g. compressed zeros) cannot be distinguished from a bomb by ratio alone; the size pre-check above is the supported guard. Truncated or forged streams that starve the decoder are detected and rejected early rather than decoded to the claimed length.