{"resultsPerPage":1,"startIndex":0,"totalResults":1,"format":"NVD_CVE","version":"2.0","timestamp":"2026-04-17T06:35:37.113","vulnerabilities":[{"cve":{"id":"CVE-2024-49940","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","published":"2024-10-21T18:15:15.703","lastModified":"2024-11-13T13:26:01.343","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nl2tp: prevent possible tunnel refcount underflow\n\nWhen a session is created, it sets a backpointer to its tunnel. When\nthe session refcount drops to 0, l2tp_session_free drops the tunnel\nrefcount if session->tunnel is non-NULL. However, session->tunnel is\nset in l2tp_session_create, before the tunnel refcount is incremented\nby l2tp_session_register, which leaves a small window where\nsession->tunnel is non-NULL when the tunnel refcount hasn't been\nbumped.\n\nMoving the assignment to l2tp_session_register is trivial but\nl2tp_session_create calls l2tp_session_set_header_len which uses\nsession->tunnel to get the tunnel's encap. Add an encap arg to\nl2tp_session_set_header_len to avoid using session->tunnel.\n\nIf l2tpv3 sessions have colliding IDs, it is possible for\nl2tp_v3_session_get to race with l2tp_session_register and fetch a\nsession which doesn't yet have session->tunnel set. Add a check for\nthis case."},{"lang":"es","value":"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: l2tp: evitar un posible desbordamiento del recuento de referencias del túnel Cuando se crea una sesión, establece un puntero hacia atrás a su túnel. Cuando el recuento de referencias de la sesión cae a 0, l2tp_session_free descarta el recuento de referencias del túnel si session->tunnel no es NULL. Sin embargo, session->tunnel se establece en l2tp_session_create, antes de que el recuento de referencias del túnel se incremente mediante l2tp_session_register, lo que deja una pequeña ventana donde session->tunnel no es NULL cuando el recuento de referencias del túnel no se ha incrementado. Mover la asignación a l2tp_session_register es trivial, pero l2tp_session_create llama a l2tp_session_set_header_len, que usa session->tunnel para obtener el encap del túnel. Agregue un argumento de encap a l2tp_session_set_header_len para evitar usar session->tunnel. Si las sesiones l2tpv3 tienen identificadores en conflicto, es posible que l2tp_v3_session_get compita con l2tp_session_register y obtenga una sesión que aún no tenga configurado session->tunnel. Agregue una verificación para este caso."}],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}]},"weaknesses":[{"source":"nvd@nist.gov","type":"Primary","description":[{"lang":"en","value":"NVD-CWE-noinfo"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.11.3","matchCriteriaId":"6D5FF9C2-A011-4A64-B614-F9244ED2EA0D"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/24256415d18695b46da06c93135f5b51c548b950","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]},{"url":"https://git.kernel.org/stable/c/f7415e60c25a6108cd7955a20b2e66b6251ffe02","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"]}]}}]}