{"id":"JLSEC-2026-95","details":"LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. In versions 1.2.1 through 1.6.55, `png_set_tRNS` and `png_set_PLTE` each alias a heap-allocated buffer between `png_struct` and `png_info`, sharing a single allocation across two structs with independent lifetimes. The `trans_alpha` aliasing has been present since at least libpng 1.0, and the `palette` aliasing since at least 1.2.1. Both affect all prior release lines `png_set_tRNS` sets `png_ptr-\u003etrans_alpha = info_ptr-\u003etrans_alpha` (256-byte buffer) and `png_set_PLTE` sets `info_ptr-\u003epalette = png_ptr-\u003epalette` (768-byte buffer). In both cases, calling `png_free_data` (with `PNG_FREE_TRNS` or `PNG_FREE_PLTE`) frees the buffer through `info_ptr` while the corresponding `png_ptr` pointer remains dangling. Subsequent row-transform functions dereference and, in some code paths, write to the freed memory. A second call to `png_set_tRNS` or `png_set_PLTE` has the same effect, because both functions call `png_free_data` internally before reallocating the `info_ptr` buffer. Version 1.6.56 fixes the issue.","modified":"2026-04-13T16:45:05.350555Z","published":"2026-04-13T16:33:44.265Z","upstream":["CVE-2026-33416"],"database_specific":{"license":"CC-BY-4.0","sources":[{"imported":"2026-04-13T16:22:04.638Z","published":"2026-03-26T17:16:38.443Z","url":"https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-33416","modified":"2026-04-02T20:28:33.973Z","html_url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33416","id":"CVE-2026-33416"}]},"references":[{"type":"WEB","url":"https://github.com/pnggroup/libpng/commit/23019269764e35ed8458e517f1897bd3c54820eb"},{"type":"WEB","url":"https://github.com/pnggroup/libpng/commit/7ea9eea884a2328cc7fdcb3c0c00246a50d90667"},{"type":"WEB","url":"https://github.com/pnggroup/libpng/commit/a3a21443ed12bfa1ef46fa0d4fb2b74a0fa34a25"},{"type":"WEB","url":"https://github.com/pnggroup/libpng/commit/c1b0318b393c90679e6fa5bc1d329fd5d5012ec1"},{"type":"WEB","url":"https://github.com/pnggroup/libpng/pull/824"},{"type":"WEB","url":"https://github.com/pnggroup/libpng/security/advisories/GHSA-m4pc-p4q3-4c7j"}],"affected":[{"package":{"name":"libpng_jll","ecosystem":"Julia","purl":"pkg:julia/libpng_jll?uuid=b53b4c65-9356-5827-b1ea-8c7a1a84506f"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.6.56+0"}]}],"database_specific":{"source":"https://github.com/JuliaLang/SecurityAdvisories.jl/tree/generated/osv/2026/JLSEC-2026-95.json"}}],"schema_version":"1.7.5"}