GHSA-4g52-pqcj-phvh

Suggest an improvement
Source
https://github.com/advisories/GHSA-4g52-pqcj-phvh
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/05/GHSA-4g52-pqcj-phvh/GHSA-4g52-pqcj-phvh.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-4g52-pqcj-phvh
Aliases
Published
2021-05-21T16:23:43Z
Modified
2023-11-08T04:04:44.779553Z
Severity
  • 5.9 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N CVSS Calculator
Summary
BLS Signature "Malleability"
Details

Impact

  1. BLS signature validation in lotus uses blst library method VerifyCompressed. This method accepts signatures in 2 forms - "serialized", and "compressed", meaning that BLS signatures can be provided as either of 2 unique byte arrays.
  2. Lotus block validation functions perform a uniqueness check on provided blocks. Two blocks are considered distinct if the CIDs of their blockheader do not match. The CID method for blockheader includes the BlockSig of the block.

The result of these issues is that it would be possible to punish miners for valid blocks, as there are two different valid block CIDs available for each block, even though this must be unique.

Patches

By switching from the go based blst bindings over to the bindings in filecoin-ffi, the code paths now ensure that all signatures are compressed by size and the way they are deserialized. This happened in https://github.com/filecoin-project/lotus/pull/5393

References

  • Original POC: https://gist.github.com/wadeAlexC/2490d522e81a796af9efcad1686e6754
References

Affected packages

Go / github.com/filecoin-project/lotus

Package

Name
github.com/filecoin-project/lotus
View open source insights on deps.dev
Purl
pkg:golang/github.com/filecoin-project/lotus

Affected ranges

Type
SEMVER
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.5.0