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Oracle Solaris 11: CVE-2021-22901 (11.4 SRU 38.101.6, 11.4 SRU 39.107.1)

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Oracle Solaris 11: CVE-2021-22901 (11.4 SRU 38.101.6, 11.4 SRU 39.107.1)



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.


  • oracle-solaris-11-4-upgrade-database-mysql-57-5-7-35-11-4-38-0-1-101-1
  • oracle-solaris-11-4-upgrade-database-mysql-57-client-5-7-35-11-4-38-0-1-101-1
  • oracle-solaris-11-4-upgrade-database-mysql-57-embedded-5-7-35-11-4-38-0-1-101-1
  • oracle-solaris-11-4-upgrade-database-mysql-57-library-5-7-35-11-4-38-0-1-101-1
  • oracle-solaris-11-4-upgrade-database-mysql-57-tests-5-7-35-11-4-38-0-1-101-1
  • oracle-solaris-11-4-upgrade-web-curl-7-79-0-11-4-39-0-1-107-0

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