redis5 security update
Redis is an advanced key-value store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets and sorted sets. You can run atomic operations on these types, like appending to a string; incrementing the value in a hash; pushing to a list; computing set intersection, union and difference; or getting the member with highest ranking in a sorted set. In order to achieve its outstanding performance, Redis works with an in-memory dataset. Depending on your use case, you can persist it either by dumping the dataset to disk every once in a while, or by appending each command to a log. Redis also supports trivial-to-setup master-slave replication, with very fast non-blocking first synchronization, auto-reconnection on net split and so forth. Other features include Transactions, Pub/Sub, Lua scripting, Keys with a limited time-to-live, and configuration settings to make Redis behave like a cache. You can use Redis from most programming languages also.
Security Fix(es):
Redis is an open source, in-memory database that persists on disk. In affected versions specially crafted Lua scripts executing in Redis can cause the heap-based Lua stack to be overflowed, due to incomplete checks for this condition. This can result with heap corruption and potentially remote code execution. This problem exists in all versions of Redis with Lua scripting support, starting from 2.6. The problem is fixed in versions 6.2.6, 6.0.16 and 5.0.14. For users unable to update an additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from executing Lua scripts. This can be done using ACL to restrict EVAL and EVALSHA commands.(CVE-2021-32626)
Redis is an open source, in-memory database that persists on disk. In affected versions an integer overflow bug in Redis can be exploited to corrupt the heap and potentially result with remote code execution. The vulnerability involves changing the default proto-max-bulk-len and client-query-buffer-limit configuration parameters to very large values and constructing specially crafted very large stream elements. The problem is fixed in Redis 6.2.6, 6.0.16 and 5.0.14. For users unable to upgrade an additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the proto-max-bulk-len configuration parameter. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command.(CVE-2021-32627)
Redis is an open source, in-memory database that persists on disk. An integer overflow bug in the ziplist data structure used by all versions of Redis can be exploited to corrupt the heap and potentially result with remote code execution. The vulnerability involves modifying the default ziplist configuration parameters (hash-max-ziplist-entries, hash-max-ziplist-value, zset-max-ziplist-entries or zset-max-ziplist-value) to a very large value, and then constructing specially crafted commands to create very large ziplists. The problem is fixed in Redis versions 6.2.6, 6.0.16, 5.0.14. An additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the above configuration parameters. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command.(CVE-2021-32628)
Redis is an open source, in-memory database that persists on disk. An integer overflow bug affecting all versions of Redis can be exploited to corrupt the heap and potentially be used to leak arbitrary contents of the heap or trigger remote code execution. The vulnerability involves changing the default set-max-intset-entries configuration parameter to a very large value and constructing specially crafted commands to manipulate sets. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. An additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the set-max-intset-entries configuration parameter. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command.(CVE-2021-32687)
Redis is an open source, in-memory database that persists on disk. When parsing an incoming Redis Standard Protocol (RESP) request, Redis allocates memory according to user-specified values which determine the number of elements (in the multi-bulk header) and size of each element (in the bulk header). An attacker delivering specially crafted requests over multiple connections can cause the server to allocate significant amount of memory. Because the same parsing mechanism is used to handle authentication requests, this vulnerability can also be exploited by unauthenticated users. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. An additional workaround to mitigate this problem without patching the redis-server executable is to block access to prevent unauthe
