A use-after-free issue was discovered in Tor 0.3.2.x before 0.3.2.10. It allows remote attackers to cause a denial of service (relay crash) because the KIST implementation allows a channel to be added more than once in the pending list.
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 Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.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://trac.torproject.org/projects/tor/ticket/24700 | issue tracking vendor advisory mitigation |
| https://trac.torproject.org/projects/tor/ticket/25117 | issue tracking patch vendor advisory |
| https://blog.torproject.org/new-stable-tor-releases-security-fixes-and-dos-prevention-03210-03110-02915 | vendor advisory |
| https://www.exploit-db.com/exploits/44994/ | exploit vdb entry third party advisory |