GHSA-g99p-47x7-mq88
HIGHgo-f3 module vulnerable to integer overflow leading to panic
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
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
Impact
Filecoin nodes consuming F3 messages are vulnerable. go-f3 panics when it validates a "poison" messages. A "poison" message can can cause integer overflow in the signer index validation. In Lotus' case, the whole node will crash.
There is no barrier to entry. An attacker doesn't need any power to pull off this attack.
These malicious messages aren't self-propagating since the bug is in the validator. An attacker needs to directly send the message to all targets.
Patches
The fix was merged and released with go-f3 0.8.7. All node software (Lotus, Forest, Venus) are using a patched version of go-f3 with their updates for the nv27 network upgrade.
go-f3 now does proper overflow checking using math.MaxInt64 comparison and returns error "justificationPower overflow" when overflow would occur.
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 initial finding(unrelated path) was reported by 0xNirix via bug bounty program which wasn't high issue. The further digging by developers led to this finding. Thank you for the contributions.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/filecoin-project/go-f3 | all versions | 0.8.7 |
Detection & 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. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/filecoin-project/go-f3 to 0.8.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-g99p-47x7-mq88 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.
How O3 protects you
O3 pinpoints whether GHSA-g99p-47x7-mq88 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-g99p-47x7-mq88. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-g99p-47x7-mq88 in your dependencies?
O3 detects GHSA-g99p-47x7-mq88 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.