CVE-2026-110240

Lancet through 2.3.9 contains an SSRF protection bypass vulnerability in netutil.IsInternalIP that misclassifies IPv6 private, link-local, CGNAT and transition addresses as external. Attackers can supply hostnames resolving to these address forms, including NAT64, 6to4 or Teredo embedding internal IPv4, to reach internal services or cloud metadata endpoints.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/duke-git/lancet
https://github.com/duke-git/lancet/blob/v1.4.6/netutil/net.go#L158-L170
https://github.com/duke-git/lancet/blob/v2.3.9/netutil/net.go#L192-L205
https://github.com/duke-git/lancet/commit/835111c832939a85416d686a1e99d5fe7060c9b4
https://github.com/duke-git/lancet/issues/356
https://github.com/duke-git/lancet/pull/357
https://www.vulncheck.com/advisories/lancet-through-2.3.9-ssrf-protection-bypass-via-netutil-isinternalip
https://github.com/duke-git/lancet/issues/356

Configurations

No configuration.

History

13 Oct 2026, 20:17

Type	Values Removed	Values Added
References	~~() https://github.com/duke-git/lancet/issues/356 -~~	() https://github.com/duke-git/lancet/issues/356 -

13 Oct 2026, 19:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 19:18

Updated : 2026-10-13 20:17

NVD link : CVE-2026-110240

Mitre link : CVE-2026-110240

CVE.ORG link : CVE-2026-110240

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

{"id": "CVE-2026-110240", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-110240", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-13T19:24:08.615533Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 4.8, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.5, "exploitabilityScore": 2.2}], "cvssMetricV40": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 6.3, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "subIntegrityImpact": "LOW", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "LOW", "vulnConfidentialityImpact": "NONE", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "disclosure@vulncheck.com", "affectedData": [{"repo": "https://github.com/duke-git/lancet", "vendor": "duke-git", "product": "lancet", "versions": [{"status": "affected", "version": "2.1.2", "versionType": "semver", "lessThanOrEqual": "2.3.9"}], "packageURL": "pkg:golang/github.com/duke-git/lancet/v2", "defaultStatus": "unaffected"}, {"repo": "https://github.com/duke-git/lancet", "vendor": "duke-git", "product": "lancet", "versions": [{"status": "affected", "version": "1.3.1", "versionType": "semver", "lessThanOrEqual": "1.4.6"}], "packageURL": "pkg:golang/github.com/duke-git/lancet", "defaultStatus": "unaffected"}]}], "published": "2026-10-13T19:18:49.350", "references": [{"url": "https://github.com/duke-git/lancet", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/duke-git/lancet/blob/v1.4.6/netutil/net.go#L158-L170", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/duke-git/lancet/blob/v2.3.9/netutil/net.go#L192-L205", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/duke-git/lancet/commit/835111c832939a85416d686a1e99d5fe7060c9b4", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/duke-git/lancet/issues/356", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/duke-git/lancet/pull/357", "source": "disclosure@vulncheck.com"}, {"url": "https://www.vulncheck.com/advisories/lancet-through-2.3.9-ssrf-protection-bypass-via-netutil-isinternalip", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/duke-git/lancet/issues/356", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "description": [{"lang": "en", "value": "CWE-918"}]}], "descriptions": [{"lang": "en", "value": "Lancet through 2.3.9 contains an SSRF protection bypass vulnerability in netutil.IsInternalIP that misclassifies IPv6 private, link-local, CGNAT and transition addresses as external. Attackers can supply hostnames resolving to these address forms, including NAT64, 6to4 or Teredo embedding internal IPv4, to reach internal services or cloud metadata endpoints."}], "lastModified": "2026-10-13T20:17:28.220", "sourceIdentifier": "disclosure@vulncheck.com"}