CVE-2026-75484

{"id": "CVE-2026-75484", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-75484", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-08-21T19:52:23.602062Z"}}], "cvssMetricV40": [{"type": "Secondary", "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 6.9, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "LOW", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "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": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "affectedData": [{"cpes": ["cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*"], "repo": "https://github.com/mtrudel/bandit", "vendor": "mtrudel", "modules": ["'Elixir.Bandit.HTTP2.Stream'"], "product": "bandit", "versions": [{"status": "affected", "version": "1.4.0", "lessThan": "1.12.5", "versionType": "semver"}], "packageURL": "pkg:hex/bandit", "packageName": "bandit", "programFiles": ["lib/bandit/http2/stream.ex"], "collectionURL": "https://repo.hex.pm", "defaultStatus": "unaffected", "programRoutines": [{"name": "'Elixir.Bandit.HTTP2.Stream':read_headers/1"}]}, {"cpes": ["cpe:2.3:a:mtrudel:bandit:*:*:*:*:*:*:*:*"], "repo": "https://github.com/mtrudel/bandit", "vendor": "mtrudel", "modules": ["'Elixir.Bandit.HTTP2.Stream'"], "product": "bandit", "versions": [{"status": "affected", "version": "fff06efe3be962b484bd4d3eb339372fda5a231f", "lessThan": "d38cf046c9a3cae4d0f88001c2ceb4143f86366b", "versionType": "git"}], "packageURL": "pkg:github/mtrudel/bandit", "packageName": "mtrudel/bandit", "programFiles": ["lib/bandit/http2/stream.ex"], "collectionURL": "https://github.com", "defaultStatus": "unaffected", "programRoutines": [{"name": "'Elixir.Bandit.HTTP2.Stream':read_headers/1"}]}]}], "published": "2026-08-20T21:17:09.597", "references": [{"url": "https://cna.erlef.org/cves/CVE-2026-75484.html", "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"}, {"url": "https://github.com/mtrudel/bandit/commit/d38cf046c9a3cae4d0f88001c2ceb4143f86366b", "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"}, {"url": "https://github.com/mtrudel/bandit/security/advisories/GHSA-x3gh-xhj4-3vq8", "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"}, {"url": "https://osv.dev/vulnerability/EEF-CVE-2026-75484", "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"}, {"url": "https://github.com/mtrudel/bandit/security/advisories/GHSA-x3gh-xhj4-3vq8", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "description": [{"lang": "en", "value": "CWE-93"}]}], "descriptions": [{"lang": "en", "value": "Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability in mtrudel bandit allows an unauthenticated remote attacker to smuggle CR, LF, or NUL characters into application-visible request headers via HTTP/2. Bandit.HTTP2.Stream.read_headers/1 validates pseudo-header placement and uniqueness, header-name casing, connection-specific headers, the te value, and content-length, but never checks field values. Because HPACK carries arbitrary octets, a HEADERS block whose field values contain \\r, \\n, or \\0 decodes without error and the values land in conn.req_headers unchanged. The HTTP/1 path already rejects the same octets; HTTP/2 did not.\n\nBandit itself is not a sink for the injected bytes: its own logging uses fixed strings or inspect, and HTTP/2 response headers are HPACK-encoded and separately rejected by Plug's put_resp_header, so response splitting is not reachable through this path. The risk is entirely in how a downstream application consumes header values, such as appending one verbatim to a plain-text log or concatenating it into an upstream request. A related gap bundled in the same fix: only :method, :scheme, and :path were checked for at most one occurrence; a duplicate :authority pseudo-header was accepted, with the first instance silently winning as conn.host while a conflicting value remained visible to the application.\n\nThis issue affects bandit: from 1.4.0 before 1.12.5."}, {"lang": "es", "value": "La vulnerabilidad de Neutralizaci\u00f3n Incorrecta de Secuencias CRLF ('Inyecci\u00f3n CRLF') en mtrudel bandit permite a un atacante remoto no autenticado introducir caracteres CR, LF o NUL en los encabezados de solicitud visibles para la aplicaci\u00f3n a trav\u00e9s de HTTP/2. Bandit.HTTP2.Stream.read_headers/1 valida la ubicaci\u00f3n y unicidad de los pseudo-encabezados, el uso de may\u00fasculas/min\u00fasculas en los nombres de los encabezados, los encabezados espec\u00edficos de la conexi\u00f3n, el valor te y la longitud del contenido, pero nunca verifica los valores de los campos. Debido a que HPACK transporta octetos arbitrarios, un bloque HEADERS cuyos valores de campo contienen \\r, \\n o \\0 se decodifica sin error y los valores llegan a conn.req_headers sin cambios. La ruta HTTP/1 ya rechaza los mismos octetos; HTTP/2 no lo hac\u00eda.\n\nBandit en s\u00ed mismo no es un sumidero para los bytes inyectados: su propio registro utiliza cadenas fijas o inspect, y los encabezados de respuesta HTTP/2 est\u00e1n codificados en HPACK y son rechazados por separado por put_resp_header de Plug, por lo que la divisi\u00f3n de respuesta no es alcanzable a trav\u00e9s de esta ruta. El riesgo reside enteramente en c\u00f3mo una aplicaci\u00f3n descendente consume los valores de los encabezados, como adjuntar uno textualmente a un registro de texto plano o concatenarlo en una solicitud ascendente. Una brecha relacionada incluida en la misma correcci\u00f3n: solo se verificaba :method, :scheme y :path para una ocurrencia como m\u00e1ximo; se aceptaba un pseudo-encabezado :authority duplicado, con la primera instancia ganando silenciosamente como conn.host mientras que un valor en conflicto permanec\u00eda visible para la aplicaci\u00f3n.\n\nEste problema afecta a bandit: desde 1.4.0 antes de 1.12.5."}], "lastModified": "2026-10-18T20:10:00.110", "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"}