CVE-2021-22901

Sažetak

curl 7.75.0 through 7.76.1 suffers from a use-after-free vulnerability resulting in already freed memory being used when a TLS 1.3 session ticket arrives over a connection. A malicious server can use this in rare unfortunate circumstances to potentially reach remote code execution in the client. When libcurl at run-time sets up support for TLS 1.3 session tickets on a connection using OpenSSL, it stores pointers to the transfer in-memory object for later retrieval when a session ticket arrives. If the connection is used by multiple transfers (like with a reused HTTP/1.1 connection or multiplexed HTTP/2 connection) that first transfer object might be freed before the new session is established on that connection and then the function will access a memory buffer that might be freed. When using that memory, libcurl might even call a function pointer in the object, making it possible for a remote code execution if the server could somehow manage to get crafted memory content into the correct place in memory.

Reference

CVSS

Base:	6.8
Impact:	6.4
Exploitability:	8.6

Pristup

Vektor	Složenost	Autentikacija
NETWORK	MEDIUM	NONE

Impact

Povjerljivost	Cjelovitost	Dostupnost
PARTIAL	PARTIAL	PARTIAL

CVSS vektor

AV:N/AC:M/Au:N/C:P/I:P/A:P

Zadnje važnije ažuriranje

27-03-2024 - 15:12

Objavljeno

11-06-2021 - 16:15