Describe CVE-2020-25725.
What is CVE-2020-25725?
In Xpdf 4.02, SplashOutputDev::endType3Char(GfxState *state) SplashOutputDev.cc:3079 is trying to use the freed `t3GlyphStack->cache`, which causes an `heap-use-after-free` problem. The codes of a previous fix for nested Type 3 characters wasn't correctly handling the case where a Type 3 char referred to another char in the same Type 3 font..