{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-101019","assignerOrgId":"9dacffd4-cb11-413f-8451-fbbfd4ddc0ab","state":"PUBLISHED","assignerShortName":"f5","dateReserved":"2026-09-30T21:56:14.632Z","datePublished":"2026-10-14T14:40:29.685Z","dateUpdated":"2026-10-15T16:43:46.354Z"},"containers":{"cna":{"affected":[{"defaultStatus":"unknown","modules":["ngx_http_js_module"],"product":"NGINX JavaScript","vendor":"F5","versions":[{"lessThan":"1.0.2","status":"affected","version":"0.7.10","versionType":"custom"}]}],"credits":[{"lang":"en","type":"finder","value":"F5"}],"datePublic":"2023-01-01T00:00:00.000Z","descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"Description
NGINX JavaScript (njs) has a vulnerability where the njs XML module exposes entity-backed XML attributes inconsistently with libxml2 canonicalization. In both the built-in njs and QuickJS backends during the canonicalization process, the $attr$Name getter may return undefined for an explicitly present attribute containing an internal entity reference. The $attrs getter may return a value derived only from the first attribute child. This may allow an unauthenticated attacker that invests significant effort in obtaining a genuinely signed document to skip validation while signature verification succeeds. An nginx-saml deployment is a confirmed affected consumer when run with the built-in njs backend.
Impact
In affected signed-XML consumers, an unauthenticated attacker can cause security-relevant attributes to appear absent or truncated while signature verification succeeds. In nginx-saml, this can bypass expiry, Destination, and request-correlation checks, enabling replay or acceptance of a response outside its intended context. It does not permit signature or identity forgery, or a direct availability impact. There is no control plane exposure; this is a data plane issue only.\n\n
Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."}],"value":"Description\nNGINX JavaScript (njs) has a vulnerability where the njs XML module exposes entity-backed XML attributes inconsistently with libxml2 canonicalization. In both the built-in njs and QuickJS backends during the canonicalization process, the $attr$Name getter may return undefined for an explicitly present attribute containing an internal entity reference. The $attrs getter may return a value derived only from the first attribute child. This may allow an unauthenticated attacker that invests significant effort in obtaining a genuinely signed document to skip validation while signature verification succeeds. An nginx-saml deployment is a confirmed affected consumer when run with the built-in njs backend.\n\nImpact\nIn affected signed-XML consumers, an unauthenticated attacker can cause security-relevant attributes to appear absent or truncated while signature verification succeeds. In nginx-saml, this can bypass expiry, Destination, and request-correlation checks, enabling replay or acceptance of a response outside its intended context. It does not permit signature or identity forgery, or a direct availability impact. There is no control plane exposure; this is a data plane issue only.\n\n\n\n Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated."}],"impacts":[{"capecId":"CAPEC-267","descriptions":[{"lang":"en","value":"CAPEC-267 Leverage Alternate Encoding"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"HIGH","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","version":"3.1"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]},{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"NETWORK","baseScore":8.3,"baseSeverity":"HIGH","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"LOW","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-436","description":"CWE-436 Interpretation Conflict","lang":"en","type":"CWE"}]}],"providerMetadata":{"orgId":"9dacffd4-cb11-413f-8451-fbbfd4ddc0ab","shortName":"f5","dateUpdated":"2026-10-14T14:40:29.685Z"},"references":[{"tags":["vendor-advisory"],"url":"https://my.f5.com/manage/s/article/K000162615"}],"source":{"discovery":"INTERNAL"},"title":"NGINX ngx_http_js_module vulnerability","workarounds":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"Applications processing signed XML should reject DTD-bearing input before calling xml.parse(). The check must cover the complete document after decoding its accepted input encoding; a parser-level DTD prohibition is preferable to a raw byte search for \"<!DOCTYPE\".
Applications should also treat absent security-relevant attributes as validation failures rather than optional values. nginx-saml deployments should explicitly validate Destination, request correlation when unsolicited SSO is not intended, assertion validity, bearer SubjectConfirmation, Recipient, and SubjectConfirmationData InResponseTo."}],"value":"Applications processing signed XML should reject DTD-bearing input before calling xml.parse(). The check must cover the complete document after decoding its accepted input encoding; a parser-level DTD prohibition is preferable to a raw byte search for \"