VulnerabilityAnalyzed

CVE-2026-73541

HIGH 8.3EPSS 0.42%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.42%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Allocation of Resources Without Limits or Throttling in ZenHive mpp allows an unauthenticated remote client to drain the fee-payer wallet through concurrent sponsored payments, denying service to legitimate payers once it is empty. MPP.Methods.Tempo.FeePayerPolicy enforces its ceilings (max_gas, max_fee_per_gas, max_priority_fee_per_gas, the worst-case gas_limit * max_fee_per_gas <= max_total_fee budget cap, and a validity window) against one transaction at a time, and nothing accounts for exposure across concurrent requests. reserve_hash_atomic/2 is keyed on the transaction hash, so it prevents duplicate broadcast of the same signed transaction but not N distinct sponsored transactions carrying distinct expiring nonces. Committed sponsor exposure is therefore N times max_total_fee, bounded by nothing in the library, and the default 900 second validity window lets co-signed transactions stay broadcastable and uncounted for that entire period. This issue affects mpp: from 0.2.0 before 0.12.0.

CVSS 4.0: 8.3 HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.42% probability · 36th percentile
CISA KEV: Not listed
Weakness: CWE-770
Affected: zenhive/machine payments protocol
Source: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

References

https://cna.erlef.org/cves/CVE-2026-73541.htmlThird Party Advisory, Mitigation
https://github.com/ZenHive/mpp/commit/ddc46868fba57ccebb567c04709812b466123076Patch
https://github.com/ZenHive/mpp/security/advisories/GHSA-j4j7-7xpr-c7crVendor Advisory
https://osv.dev/vulnerability/EEF-CVE-2026-73541Third Party Advisory, Mitigation

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.