CVE-2022-23495: go-merkledag implements the 'DAGService' interface and adds two ipld node types, Protobuf and Raw for the ipfs project. A `ProtoNode` may be modified ...

Description

go-merkledag implements the 'DAGService' interface and adds two ipld node types, Protobuf and Raw for the ipfs project. A `ProtoNode` may be modified in such a way as to cause various encode errors which will trigger a panic on common method calls that don't allow for error returns. A `ProtoNode` should only be able to encode to valid DAG-PB, attempting to encode invalid DAG-PB forms will result in an error from the codec. Manipulation of an existing (newly created or decoded) `ProtoNode` using the modifier methods did not account for certain states that would place the `ProtoNode` into an unencodeable form. Due to conformance with the [`github.com/ipfs/go-block-format#Block`](https://pkg.go.dev/github.com/ipfs/go-block-format#Block) and [`github.com/ipfs/go-ipld-format#Node`](https://pkg.go.dev/github.com/ipfs/go-ipld-format#Node) interfaces, certain methods, which internally require a re-encode if state has changed, will panic due to the inability to return an error. This issue has been addressed across a number of pull requests. Users are advised to upgrade to version 0.8.1 for a complete set of fixes. Users unable to upgrade may attempt to mitigate this issue by sanitising inputs when allowing user-input to set a new `CidBuilder` on a `ProtoNode` and by sanitising `Tsize` (`Link#Size`) values such that they are a reasonable byte-size for sub-DAGs where derived from user-input.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

1.25%

65.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Protocol	Go-Merkledag	>= 0.4.0, < 0.8.1

References

https://en.wikipedia.org/wiki/Directed_acyclic_graphTechnical Description, Third Party Advisory
https://github.com/ipfs/go-merkledag/issues/90Patch, Third Party Advisory
https://github.com/ipfs/go-merkledag/pull/91Patch, Third Party Advisory
https://github.com/ipfs/go-merkledag/pull/92Patch, Third Party Advisory
https://github.com/ipfs/go-merkledag/pull/93Patch, Third Party Advisory
https://github.com/ipfs/go-merkledag/releases/tag/v0.8.0Release Notes, Third Party Advisory
https://github.com/ipfs/go-merkledag/releases/tag/v0.8.1Release Notes, Third Party Advisory
https://github.com/ipfs/go-merkledag/security/advisories/GHSA-x39j-h85h-3f46Third Party Advisory
https://github.com/ipfs/kubo/issues/9297Patch, Third Party Advisory
https://en.wikipedia.org/wiki/Directed_acyclic_graphTechnical Description, Third Party Advisory
https://github.com/ipfs/go-merkledag/issues/90Patch, Third Party Advisory
https://github.com/ipfs/go-merkledag/pull/91Patch, Third Party Advisory
https://github.com/ipfs/go-merkledag/pull/92Patch, Third Party Advisory
https://github.com/ipfs/go-merkledag/pull/93Patch, Third Party Advisory
https://github.com/ipfs/go-merkledag/releases/tag/v0.8.0Release Notes, Third Party Advisory
https://github.com/ipfs/go-merkledag/releases/tag/v0.8.1Release Notes, Third Party Advisory
https://github.com/ipfs/go-merkledag/security/advisories/GHSA-x39j-h85h-3f46Third Party Advisory
https://github.com/ipfs/kubo/issues/9297Patch, Third Party Advisory

Timeline

Published: Dec 8, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-23495?

go-merkledag implements the 'DAGService' interface and adds two ipld node types, Protobuf and Raw for the ipfs project. A `ProtoNode` may be modified in such a way as to cause various encode errors which will trigger a panic on common method calls that don't allow for error returns. A `ProtoNode` should only be able to encode to valid DAG-PB, attempting to encode invalid DAG-PB forms will result in an error from the codec. Manipulation of an existing (newly created or decoded) `ProtoNode` using the modifier methods did not account for certain states that would place the `ProtoNode` into an unencodeable form. Due to conformance with the [`github.com/ipfs/go-block-format#Block`](https://pkg.go.dev/github.com/ipfs/go-block-format#Block) and [`github.com/ipfs/go-ipld-format#Node`](https://pkg.go.dev/github.com/ipfs/go-ipld-format#Node) interfaces, certain methods, which internally require a re-encode if state has changed, will panic due to the inability to return an error. This issue has been addressed across a number of pull requests. Users are advised to upgrade to version 0.8.1 for a complete set of fixes. Users unable to upgrade may attempt to mitigate this issue by sanitising inputs when allowing user-input to set a new `CidBuilder` on a `ProtoNode` and by sanitising `Tsize` (`Link#Size`) values such that they are a reasonable byte-size for sub-DAGs where derived from user-input.

How severe is CVE-2022-23495?

CVE-2022-23495 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.25% probability of exploitation in the next 30 days.

How do I fix CVE-2022-23495?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.