mpp: Allocation of Resources Without Limits or Throttling
CVE-2026-73541 is a high-severity allocation of resources without limits or throttling vulnerability in mpp from ZenHive, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 0.12.0, ddc46868fba57ccebb567c04709812b466123076 as the first without the flaw, so updating mpp to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.59% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update mpp to 0.12.0 or ddc46868fba57ccebb567c04709812b466123076, whichever matches your release line, or a later version.
- Update Machine Payments Protocol to 0.12.0 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| ZenHive | mpp | 0.2.0 up to, but not including, 0.12.0; d29d54e507918db00a5b65d90136b73166c017d7 up to, but not including, ddc46868fba57ccebb567c04709812b466123076 | 0.12.0, ddc46868fba57ccebb567c04709812b466123076 |
| Zenhive | Machine Payments Protocol | 0.2.0 up to, but not including, 0.12.0 | 0.12.0 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- LowLimited modification of data is possible.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.3 | High | CNA |
| CVSS 3.1 | 8.2 | High | NVD |
Official 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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Allocation of Resources Without Limits or Throttling
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
How developers prevent this class of flaw
- Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.
- Limit the amount of resources that are accessible to unprivileged users. Set per-user limits for resources. Allow the system administrator to define these limits. Be careful to avoid CWE-410.
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
More Allocation of Resources Without Limits or Throttling vulnerabilities (CWE-770)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- cna.erlef.org/cves/CVE-2026-73541.htmlThird Party Advisory, Mitigation
- github.com/ZenHive/mpp/commit/ddc46868fba57ccebb567c04709812b466123076
- osv.dev/vulnerability/EEF-CVE-2026-73541Third Party Advisory, Mitigation
Other vulnerabilities in mpp
- 7.1 High severity
- 8.2 High severity
- 8.3 High severity
- 8.3 High severity
- 7.5 High severity
- 7.5 High severity
Recent Allocation of Resources Without Limits or Throttling vulnerabilities
- 8.7 High severity
- 7.5 High severity
- 8.7 High severity
- 9.8 Critical severity
- 7.5 High severity
- 8.7 High severity
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