CVE-2026-40583Public exploitNetwork attack vector

Node shutdown via pre-authorization state mutation

Published Apr 21, 2026 · Updated Apr 21, 2026

Incorrect behavior order in UltraDAG Core 0.1 allows remote attackers to shut down validator nodes via a signed SmartOp vote transaction. apply_smart_op_tx debits the fee and increments the sender nonce before checking council membership, and its error handler increments the nonce again. A funded, non-council smart account with a valid signing key is sufficient; finalization detects the resulting supply mismatch and exits the node.

CVSS severity8.8
High
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect behavior order in UltraDAG Core 0.1 allows remote attackers to shut down validator nodes via a signed SmartOp vote transaction. apply_smart_op_tx debits the fee and increments the sender nonce before checking council membership, and its error handler increments the nonce again. A funded, non-council smart account with a valid signing key is sufficient; finalization detects the resulting supply mismatch and exits the node.

The record

CVE
CVE-2026-40583
Published
Apr 21, 2026
Updated
Apr 21, 2026
Vendor
UltraDAG
Product
UltraDAG Core
Classifications
CWE-460, CWE-696, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion== 0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

UltraDAG · UltraDAG Coreversion== 0.1

Published CVSS scores

8.8GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
8.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-460Improper Cleanup on Thrown Exception
CWE-696Incorrect Behavior Order
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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