| Package | Affected versions | Patched versions |
|---|---|---|
| vyper | < 0.4.0 | 0.4.0 |
| vyper | < 0.4.0 | 0.4.0 |
Incorrect values can be logged when raw_log builtin is called with memory or storage arguments to be used as topics.
A contract search was performed and no vulnerable contracts were found in production. In particular, no uses of raw_log() were found at all in production; it is apparently not a well-known function.
The build_IR function of the RawLog class fails to properly unwrap the variables provided as topics. Consequently, incorrect values are logged as topics.
x: bytes32
@external
def f():
self.x = 0x1234567890123456789012345678901234567890123456789012345678901234
raw_log([self.x], b"") # LOG1(offset:0x60, size:0x00, topic1:0x00)
y: bytes32 = 0x1234567890123456789012345678901234567890123456789012345678901234
raw_log([y], b"") # LOG1(offset:0x80, size:0x00, topic1:0x40)
Fixed in https://github.com/vyperlang/vyper/pull/3977.
Incorrect values can be logged which may result in unexpected behavior in client-side applications relying on these logs.
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