CVE Explorer

CVE-2026-1664

Summary An Insecure Direct Object Reference has been found to exist in `createHeaderBasedEmailResolver()` function within the Cloudflare Agents SDK. The issue occurs because the `Message-ID` and `References` headers are parsed to derive the target agentName and agentId without proper validation or origin checks, allowing an external attacker with control of these headers to route inbound mail to arbitrary Durable Object instances and namespaces . Root cause The `createHeaderBasedEmailResol

Lifecycle PUBLISHED1 preserved revisionFact urn:baitaphish:canonical-cve-fact-revision:v2:fa383139bbbd95c70a9ab7806be47baae59b0822062148cbb8961031013aedbf

Known exploited

Not asserted

Disputed

Stale source

Conflicts

Affected products and versions

1 source assertion

{"collectionURL":"https://github.com/cloudflare/agents","defaultStatus":"unaffected","packageName":"agents","repo":"https://github.com/cloudflare/agents","versions":[{"lessThanOrEqual":"0.3.6","status":"affected","version":"0.0.104","versionType":"semver"}]}

cve_program_cvelist_v5affected
urn:baitaphish:normalized-source-record:v2:4d6b383988f252ffda81ec395174f73434d4bf10fca5ac99a03871bc19d3287e · sha256:8dcb349c487c39fd… · /containers/cna/affected/0

Provider-owned CVSS observations

1 source assertion

{"metric":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":6.9,"baseSeverity":"MEDIUM","exploitMaturity":"NOT_DEFINED","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"LOW","subIntegrityImpact":"LOW","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"…

cve_program_cvelist_v5cvss
urn:baitaphish:normalized-source-record:v2:4d6b383988f252ffda81ec395174f73434d4bf10fca5ac99a03871bc19d3287e · sha256:8dcb349c487c39fd… · /containers/cna/metrics/0/cvssV4_0

CWE assertions

1 source assertion

{"cweId":"CWE-639","description":"CWE-639 Authorization Bypass Through User-Controlled Key","lang":"en","type":"CWE"}

cve_program_cvelist_v5cwe
urn:baitaphish:normalized-source-record:v2:4d6b383988f252ffda81ec395174f73434d4bf10fca5ac99a03871bc19d3287e · sha256:8dcb349c487c39fd… · /containers/cna/problemTypes/0/descriptions/0

Source references

1 source assertion

{"url":"https://github.com/cloudflare/agents"}

cve_program_cvelist_v5reference
urn:baitaphish:normalized-source-record:v2:4d6b383988f252ffda81ec395174f73434d4bf10fca5ac99a03871bc19d3287e · sha256:8dcb349c487c39fd… · /containers/cna/references/0

Attribution and limitations

CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →

Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.

← Back to CVE Explorer