Decoding a paletted BMP file with an out-of-range palette index results in a panic when accessing pixels in the invalid image.

References

• https://go.dev/cl/781500
• https://go.dev/issue/79576
• https://groups.google.com/g/golang-announce/c/uhYX90BlBvI
• https://pkg.go.dev/vuln/GO-2026-5031