CVE-2025-59942 — go-f3
HIGHCVE-2025-59942 is a high-severity (CVSS 7.5) CWE-190 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.
go-f3 module vulnerable to integer overflow leading to panic
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- 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 CVE-2025-59942.
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
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 | 0.8.7go get github.com/filecoin-project/go-f3@v0.8.7 |
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 0.8.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-59942 is resolved across your whole dependency graph.
Workarounds
Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.
Frequently Asked Questions
Is CVE-2025-59942 in your dependencies?
Find it across Go, including transitive dependencies.