Attacker Impact
CVE-2020-28271 affects deephas versions 1.0.0 through 1.0.5 [S1][S2]. If a deployed application passes attacker-controlled object paths or property names into affected deephas code, prototype pollution can alter inherited object behavior and may lead to denial of service or gadget-dependent code execution [S1][S2]. A dependency match by itself does not prove that this runtime path exists in production.
Root Cause
Affected deephas releases did not sufficiently block prototype-sensitive object path segments during deep object path handling [S1][S2]. That library behavior is the advisory condition; application impact depends on whether untrusted input can reach those calls and whether the surrounding application has exploitable prototype-pollution gadgets.
Concrete Fixes
- Upgrade or replace the dependency: Upgrade deephas to the latest published release or replace it with a maintained deep-path utility, then regenerate the active lockfile and redeploy the built artifact [S2].
- Verify the deployed runtime: Confirm the package version in the lockfile, built image, and production dependency tree. A fixed manifest does not close the advisory if an old lockfile or cached image layer still installs an affected version.
- Review input paths: Audit call sites that pass user-controlled keys, object paths, or JSON property names into deep-path helpers. Reject prototype-sensitive keys before object mutation and keep schema validation close to the request boundary.
What FixVibe checks
FixVibe GitHub repo scans now check dependency manifests and lockfiles for deephas version evidence in the affected range [S1][S2]. Findings are reported as version-based advisories with file path, detected version or constraint, advisory source quality, confidence, and the runtime conditions FixVibe did not verify.
The check is static-only: FixVibe does not send prototype-pollution payloads, mutate Object.prototype, or confirm denial-of-service or code-execution behavior on the running application.