OpenEXR is the reference implementation and specification for the EXR image format, widely used in the motion picture industry. Versions 3.3.0 through 3.3.12 and 3.4.0 through 3.4.13 contain a heap buffer overflow in PyOpenEXR triggered by a channel-name key collision between literal and prefixed RGB channels. When separate_channels=false, PyOpenEXR maps each physical channel name through channelNameToRGBA() and coalesces the results into a shared RGB array. A crafted flat scanline EXR that contains both a literal channel such as left and prefixed channels such as left.R, left.G, and left.B causes these names to collide, so the wrapper reuses an undersized two-dimensional NumPy array for the coalesced RGB slices and writes out of bounds when OpenEXR.File(path) decodes the pixels. This issue is fixed in versions 3.3.13 and 3.4.14.