In Netwide Assembler (NASM) 2.14rc0, there are multiple heap use after free vulnerabilities in the tool nasm. The related heap is allocated in the token() function and freed in the detoken() function (called by pp_getline()) - it is used again at multiple positions later that could cause multiple damages. For example, it causes a corrupted double-linked list in detoken(), a double free or corruption in delete_Token(), and an out-of-bounds write in detoken(). It has a high possibility to lead to a remote code execution attack.
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
| Link | Tags |
|---|---|
| https://usn.ubuntu.com/3694-1/ | third party advisory vendor advisory |
| https://bugzilla.nasm.us/show_bug.cgi?id=3392414 | issue tracking patch exploit vdb entry third party advisory |
| https://security.gentoo.org/glsa/201903-19 | vendor advisory |