Avro

iskorotkov/avro is a fast Go Avro codec. Prior to 2.33.0, the Avro array and map decoders looped over an attacker-controlled block-count value without checking the underlying reader's error state inside the loop body. Reader.ReadBlockHeader returns the count as a Go int, which is 64-bit on amd64 / arm64 targets — so a producer can declare a block of up to math.MaxInt64 (~9.2 × 10¹⁸) elements followed by EOF (or any truncated payload), and the decoder will attempt that many no-op iterations before propagating the error. The realistic ceiling is "indefinite until the worker is killed externally" — a single hostile payload pins a CPU core until the process is OOM-killed, deadline-cancelled, or terminated. Remote, unauthenticated denial-of-service. This vulnerability is fixed in 2.33.0.

Published: 2026-05-29T19:58:59.667Z
Updated: 2026-09-09T12:05:07.261Z

iskorotkov/avro is a fast Go Avro codec. Prior to 2.33.0, several Avro decoder paths read attacker-controlled 64-bit values from the wire format and either narrowed them to platform-sized int before bounds-checking, or summed them with overflow-prone signed-int arithmetic. On 32-bit targets (GOARCH=386, arm, mips, wasm, etc.), the truncation paths can silently bypass byte-slice limits, select the wrong union branch, or hit the OCF negative-make panic via wrap. Three sub-issues are not 32-bit-specific: cumulative-size arithmetic overflow in arrayDecoder.Decode / mapDecoder.Decode / mapDecoderUnmarshaler.Decode (wraps at math.MaxInt64 on amd64 / arm64 and bypasses MaxSliceAllocSize / MaxMapAllocSize), math.MinInt negation in block-header handling, and make([]byte, size) with a negative size in OCF block reads — all three panic or bypass caps on any platform, giving an attacker a denial-of-service primitive there. This vulnerability is fixed in 2.33.0.

Published: 2026-05-29T19:58:21.535Z
Updated: 2026-09-09T12:04:43.443Z