A flaw has been found in pnggroup libpng up to 1.6.55. Affected by this vulnerability is the function do_pnm2png of the file contrib/pngminus/pnm2png.c of the component pnm2png. This manipulation of the argument width/height causes heap-based buffer overflow. The attack is restricted to local execution. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.

The remote NewStart CGSL host, running version MAIN 7.02, has libpng packages installed that are affected by multiple vulnerabilities:

  - A flaw has been found in pnggroup libpng up to 1.6.55. Affected by this vulnerability is the function     do_pnm2png of the file contrib/pngminus/pnm2png.c of the component pnm2png. This manipulation of the     argument width/height causes heap-based buffer overflow. The attack is restricted to local execution. The     exploit has been published and may be used. The project was informed of the problem early through an issue     report but has not responded yet. (CVE-2026-3713)

  - LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable     Network Graphics) raster image files. Prior to 1.6.55, an out-of-bounds read vulnerability exists in the     png_set_quantize() API function. When the function is called with no histogram and the number of colors in     the palette is more than twice the maximum supported by the user's display, certain palettes will cause     the function to enter into an infinite loop that reads past the end of an internal heap-allocated buffer.
    The images that trigger this vulnerability are valid per the PNG specification. This vulnerability is     fixed in 1.6.55. (CVE-2026-25646)

  - LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable     Network Graphics) raster image files. Prior to version 1.6.51, a heap buffer over-read vulnerability     exists in libpng's png_do_quantize function when processing PNG files with malformed palette indices. The     vulnerability occurs when palette_lookup array bounds are not validated against externally-supplied image     data, allowing an attacker to craft a PNG file with out-of-range palette indices that trigger out-of-     bounds memory access. This issue has been patched in version 1.6.51. (CVE-2025-64505)

  - LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable     Network Graphics) raster image files. From version 1.6.0 to before 1.6.51, a heap buffer over-read     vulnerability exists in libpng's png_write_image_8bit function when processing 8-bit images through the     simplified write API with convert_to_8bit enabled. The vulnerability affects 8-bit grayscale+alpha,     RGB/RGBA, and images with incomplete row data. A conditional guard incorrectly allows 8-bit input to enter     code expecting 16-bit input, causing reads up to 2 bytes beyond allocated buffer boundaries. This issue     has been patched in version 1.6.51. (CVE-2025-64506)

  - LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable     Network Graphics) raster image files. From version 1.6.0 to before 1.6.51, an out-of-bounds read     vulnerability exists in png_image_read_composite when processing palette images with     PNG_FLAG_OPTIMIZE_ALPHA enabled. The palette compositing code in png_init_read_transformations incorrectly     applies background compositing during premultiplication, violating the invariant component  alpha  257     required by the simplified PNG API. This issue has been patched in version 1.6.51. (CVE-2025-64720)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

An update of the libpng package has been released.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - A flaw has been found in pnggroup libpng up to 1.6.55. Affected by this vulnerability is the function     do_pnm2png of the file contrib/pngminus/pnm2png.c of the component pnm2png. This manipulation of the     argument width/height causes heap-based buffer overflow. The attack is restricted to local execution. The     exploit has been published and may be used. The project was informed of the problem early through an issue     report but has not responded yet. (CVE-2026-3713)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
343581	NewStart CGSL MAIN 7.02 : libpng Multiple Vulnerabilities (NS-SA-2026-0100)	Nessus	NewStart CGSL Local Security Checks	Local	high
333963	Photon OS 5.0: Libpng PHSA-2026-5.0-91-0802	Nessus	PhotonOS Local Security Checks	Local	medium
305121	Photon OS 5.0: Libpng PHSA-2026-5.0-0802	Nessus	PhotonOS Local Security Checks	Local	medium
301483	Linux Distros Unpatched Vulnerability : CVE-2026-3713	Nessus	Misc.	Local	medium

Detections

Analytics

CVE-2026-3713

medium

Tenable Plugins

high

medium

medium

medium