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

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.2 · CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-42328: 0.12% estimated exploitation activity in the next 30 days; percentile 1.84 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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…

Published by the source

7 May 2026, 02:07 UTC

Last modified by the source

8 Jun 2026, 23:47 UTC

Source last checked

26 Oct 2026, 15:23 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-w239-58x2-q8p5

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# Patch Next advisory brief: CVE-2026-42328

Advisory: go-ipld-prime's DAG-CBOR and DAG-JSON decoders have unbounded recursion depth
IDs: CVE-2026-42328, GHSA-w239-58x2-q8p5
Record: https://patchnext.com/advisories/cve-2026-42328 (revision 1, source checked 26 Oct 2026, 15:23 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.2)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/ipld/go-ipld-prime 0.23.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/ipld/go-ipld-prime: affected < 0.23.0; fixed in 0.23.0

## Suggested inspection (read-only)
- Go github.com/ipld/go-ipld-prime: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/ipld/go-ipld-prime.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-w239-58x2-q8p5 (GitHub-reviewed advisory GHSA-w239-58x2-q8p5 lists affected ranges: Go github.com/ipld/go-ipld-prime >=0 <0.23.0)

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