In opencv/modules/imgcodecs/src/grfmt_pxm.cpp, function PxMDecoder::readData has an integer overflow when calculate src_pitch. If the image is from remote, may lead to remote code execution or denial of service. This affects Opencv 3.3 and earlier.
https://security.gentoo.org/glsa/201712-02
https://lists.debian.org/debian-lts-announce/2021/10/msg00028.html
https://lists.debian.org/debian-lts-announce/2018/07/msg00030.html