Lodestar snappy decompression issue

Exploitation

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

CVSS

not scored

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Impact Unintended permanent chain split affecting greater than or equal to 25% of the network, requiring hard fork (network partition requiring hard fork) Description Lodestar client may fail to decode snappy framing compressed messages. Vulnerability Details In Req/Resp protocol the message are encoded by using sszsnappy encoding, which is basically snappy framing compression over ssz encoded message. It's mentioned here - https://github.com/ethereum/consensus-specs/blob/dev/specs/phase0/p2p-interface.md In snappy framing format there a few types of chunks. We are interested in so called reserved skippable chunks. These are chunks with chunk type in range [0x80, 0xfd] Let's see how rust snappy handles them https://github.com/BurntSushi/rust-snappy/blob/master/src/read.rs#L137 Similar code can be found in golang implementation - https://github.com/golang/snappy/blob/master/decode.go#L221 Now let's see how lodestar handles such chunks…

Published by the source

14 Jan 2025, 22:03 UTC

Last modified by the source

14 Jan 2025, 22:04 UTC

Source last checked

26 Oct 2026, 12:31 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-53rv-hcvm-rpp9

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-53rv-hcvm-rpp9

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# Patch Next advisory brief: GHSA-53rv-hcvm-rpp9

Advisory: Lodestar snappy decompression issue
IDs: GHSA-53rv-hcvm-rpp9
Record: https://patchnext.com/advisories/ghsa-53rv-hcvm-rpp9 (revision 2, source checked 26 Oct 2026, 12:31 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Unrated
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @lodestar/reqresp 1.25.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @lodestar/reqresp: affected < 1.25.0; fixed in 1.25.0

## Suggested inspection (read-only)
- `npm ls @lodestar/reqresp --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## 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 @lodestar/reqresp.
- 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://osv.dev/vulnerability/GHSA-53rv-hcvm-rpp9 (OSV record GHSA-53rv-hcvm-rpp9 lists affected ranges: npm @lodestar/reqresp >=0 <1.25.0 (fixed))
- Verified: https://github.com/advisories/GHSA-53rv-hcvm-rpp9 (GitHub-reviewed advisory GHSA-53rv-hcvm-rpp9 lists affected ranges: npm @lodestar/reqresp >=0 <1.25.0)

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