go-f3 Vulnerable to Cached Justification Verification BypassGHSA-7pq9-rf9p-wcrf
MEDIUMFix: filecoin-project/go-f3@76fff18GHSA-7pq9-rf9p-wcrf is a medium-severity (CVSS 5.9) CWE-305 vulnerability in github.com/filecoin-project/go-f3. A fix is available for github.com/filecoin-project/go-f3 — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-7pq9-rf9p-wcrf.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/filecoin-project/go-f3Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Description
A vulnerability exists in go-f3's justification verification caching mechanism where verification results are cached without properly considering the context of the message. An attacker can bypass justification verification by:
- First submitting a valid message with a correct justification
- Then reusing the same cached justification in contexts where it would normally be invalid
This occurs because the cached verification does not properly validate the relationship between the justification and the specific message context it's being used with.
Impact
- Potential consensus integrity issues through invalid justification acceptance
- Could affect network liveness if exploited systematically
- May allow malicious actors to influence consensus decisions with invalid justifications
- Requires significant power (350+ TiB due to power table rounding) to meaningfully exploit
- It would also be difficult to exploit in a synchronised fashion, such that >1/3 of the network goes down at one time. This isn't a one-msg panic, where you can spam it and bring everyone down, because every node will have a different amount of memory andmany SPs also run redundant lotus nodes.
Patches
The fix was merged and released with go-f3 0.8.9. All node software (Lotus, Forest, Venus) are using a patched version of go-f3 with their updates for the nv27 network upgrade.
Workarounds
The are no immediate workarounds available. Nodes should upgrade to the patched version, which they will have done if participating in nv27 on Filecoin mainnet.
Credits
The bug was reported by @lgprbs via our bug bounty program. Thank you for the contributions.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/filecoin-project/go-f3 | all versions | 0.8.9go get github.com/filecoin-project/go-f3@v0.8.9 |
Affected Products
go-f3filecoinDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/filecoin-project/go-f3, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/filecoin-project/go-f3 to 0.8.9 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-7pq9-rf9p-wcrf is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is GHSA-7pq9-rf9p-wcrf in your dependencies?
Find it across Go, including transitive dependencies.