Vulnerability feed

_gx_multi_line_text_view_display_info_get() reads one byte past the end of the application's text buffer when the string it is given ends with a carriage return (\r). The over-read can also cause callers to advance their index past the end of the string, producing a second over-read in _gx_multi_line_text_view_string_total_rows_compute() and a row of text that is not in the source.

The GUIX software JPEG decoder reads four kinds of marker segment without checking that each is long enough to hold what it reads. A truncated segment is therefore read past the end of the caller's image buffer. Separately, a zero chroma sampling factor makes the block decode loop non-terminating. Both reproduce in the default configuration, in which GX_SOFTWARE_DECODER_SUPPORT is enabled.

_gx_binres_pixelmap_table_load() in the GUIX binary resource (theme) loader indexes the pixelmap table with a value read verbatim from the resource file and never bounds it against the table size. A crafted theme drives a write of up to roughly 256 KB past the end of the table.

The overflowed buffer is allocated by GUIX itself, through _gx_system_memory_allocator, rather than supplied by the caller, so the loader corrupts its own arena. The public API gx_binres_theme_load() takes no size parameter, so no amount of caller diligence prevents this.

Reproduces in the shipped default configuration; GX_BINARY_RESOURCE_SUPPORT is enabled by default.

gx_binres_theme_load() and gx_binres_font_load() take the resource as a bare GX_UBYTE * with no length, and GX_BINRES_DATA_INFO has no field to carry one. Every read is therefore performed at an offset the file itself chose, against a buffer whose extent the loader does not know. A resource that declares more data than it contains is read past its end, and an offset stored in the file is turned into a pointer without being bounded.

This is a distinct defect from GHSA-hgcj-22cg-4hfv, which was an underflowed glyph count. It needs no underflow and no wrapped multiply: a perfectly well-formed, narrow glyph range reaches it.

The GUIX binary resource loader never checks that a font page's glyph range is well formed. gx_page_header_first_glyph and gx_page_header_last_glyph are read verbatim from the file and only the upper bound of last_glyph is validated, so a page declaring first_glyph > last_glyph makes last - first + 1 underflow to a very large unsigned count.

That count is multiplied by a glyph record size to reserve the load buffer, and the multiply is unchecked, so it wraps to a small value and the loader allocates a buffer far smaller than the data it is about to write. The load pass then recomputes the count in a narrower type and writes attacker-controlled glyph records into the undersized buffer.

The PNG chunk reader has no notion of chunk ordering. It records whether an IDAT has been seen and whether a tRNS has already supplied transparency, but nothing prevents an IHDR being read a second time.

A PNG carries exactly one IHDR and it is the first chunk. A file that places a second one after IDAT rewrites the image width, height, bit depth and pixel depth *after* the decoded-data buffer has already been allocated and filled from the original values. The pass that reverses the PNG row filters then derives its own extent from the new dimensions and walks the old allocation, moving image bytes past the end of it.

The buffer is allocated by GUIX rather than supplied by the caller, so the application has no way to size it defensively. The decoder is compiled in by default.

The GUIX JPEG software decoder enforces no ordering on JPEG markers. A file that places a second SOF0 frame header after SOS re-runs the frame header parser after the output buffer has already been allocated and its geometry latched. The decoder returns GX_SUCCESS and publishes a GX_PIXELMAP whose reported dimensions and data_size exceed the allocation behind it.

Any consumer that trusts the returned structure reads out of bounds, including GUIX's own display drivers, reached through the ordinary draw path.

Reproduces in the shipped default configuration; GX_SOFTWARE_DECODER_SUPPORT is enabled by default.