GHSA-hfmf-q43v-2ffj is a high-severity (CVSS 7.5) CWE-347 vulnerability in openpgp. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether GHSA-hfmf-q43v-2ffj is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Improper Key Verification in openpgp
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
openpgpnpmDescription
Versions of openpgp prior to 4.2.0 are vulnerable to Improper Key Verification. The OpenPGP standard allows signature packets to have subpackets which may be hashed or unhashed. Unhashed subpackets are not cryptographically protected and cannot be trusted. The openpgp package does not verify whether a subpacket is hashed. Furthermore, due to the order of parsing a signature packet information from unhashed subpackets overwrites information from hashed subpackets. This may allow an attacker to modify the contents of a key certification signature or revocation signature. Doing so could convince a victim to use an obsolete key for encryption. An attack require a victim to import a manipulated key or update an existing key with a manipulated version.
Recommendation
Upgrade to version 4.2.0 or later.
If you are upgrading from a version <4.0.0 it is highly recommended to read the High-Level API Changes section of the openpgp 4.0.0 release: https://github.com/openpgpjs/openpgpjs/releases/tag/v4.0.0
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | openpgp | all versions | 4.2.0 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for openpgp. 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 openpgp to 4.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hfmf-q43v-2ffj 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-hfmf-q43v-2ffj 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-hfmf-q43v-2ffj. 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-hfmf-q43v-2ffj in your dependencies?
O3 detects GHSA-hfmf-q43v-2ffj across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.