CVE-2026-42328

MEDIUM6.2EPSS 0.02%

go-ipld-prime's DAG-CBOR and DAG-JSON decoders have unbounded recursion depth

發布日:2026/5/7修改日:2026/5/7

描述

The DAG-CBOR and DAG-JSON decoders recurse on each nested map or list without a depth limit. A payload containing deeply nested collections causes the decoder to recurse once per level, growing the goroutine stack until the Go runtime terminates the process with a fatal stack overflow (distinct from a recoverable panic). For DAG-CBOR, a payload of approximately 2 MB, consisting of repeated `0x81` (array-of-1) bytes followed by a terminator, produces around 2 million recursion frames and reliably exhausts Go's default 1 GB goroutine stack. The existing allocation budget does not prevent this: each nested collection header costs only a handful of budget units, so the stack is exhausted before the budget is. DAG-JSON has equivalent exposure via `[[[...]]]`-style payloads; it has no budget system and is therefore unprotected against recursion depth as well. Schema-free decoding (using `basicnode.Prototype.Any`) allows arbitrary nesting depth. Schema-bound decoding bounds nesting only when the schema itself is non-recursive and contains no fields typed as `Any`; schemas with recursive type references or any `Any`-typed fields permit unconstrained nesting at those points. The fix adds a configurable `MaxDepth` option to both decoders, defaulting to 1024 nested levels. The decoder returns `ErrDecodeDepthExceeded` when a payload nests beyond the limit. Well-formed IPLD data rarely approaches this depth in practice; the default is generous for legitimate use while preventing stack exhaustion.

受影響套件(1)

CVSS 分數

來源版本嚴重程度向量
osvCVSS 3.1MEDIUM6.2CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

參考連結(2)