CVE-2021-21401

EIP tracks 1 public exploit for CVE-2021-21401. PoCs published by uthrasri.

AI-analyzed exploit summary The repository contains the nanopb library source code and examples but lacks any exploit code or technical analysis related to CVE-2021-21401. It appears to be a placeholder or mislabeled repository.

Nanopb is a small code-size Protocol Buffers implementation in ansi C. In Nanopb before versions 0.3.9.8 and 0.4.5, decoding a specifically formed message can cause invalid `free()` or `realloc()` calls if the message type contains an `oneof` field, and the `oneof` directly contains both a pointer field and a non-pointer field. If the message data first contains the non-pointer field and then the pointer field, the data of the non-pointer field is incorrectly treated as if it was a pointer value. Such message data rarely occurs in normal messages, but it is a concern when untrusted data is parsed. This has been fixed in versions 0.3.9.8 and 0.4.5. See referenced GitHub Security Advisory for more information including workarounds.