CVE-2025-21768

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I'm not sure if rpl and seg6\ncan actually hit this, but in principle I don't see why not."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: ipv6: arreglo de bucles de referencia dst en lwtunnels rpl, seg6 y ioam6 Algunos lwtunnels tienen una cach\u00e9 dst para dst posterior a la transformaci\u00f3n. Si el destino del paquete no cambi\u00f3, podemos terminar registrando una referencia al lwtunnel en su propia cach\u00e9, y el estado del lwtunnel nunca se liberar\u00e1. Descubierto por la prueba ioam6.sh, kmemleak se corrigi\u00f3 recientemente para detectar fugas de memoria por CPU. No estoy seguro de si rpl y seg6 realmente pueden alcanzar esto, pero en principio no veo por qu\u00e9 no."}], "id": "CVE-2025-21768", "lastModified": "2026-11-05T21:17:42.660", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-21768", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-11-05T20:35:07.894523Z", "version": "2.0.3"}}]}, "published": "2025-02-27T03:15:17.480", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/26f0b472ae2a82920e38c7cf41583951046d586a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/4c0f200c7d06fedddde82209c099014d63f4a6c0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/5ab11a4e219e93b8b31a27f8ec98d42afadd8b7a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/92191dd1073088753821b862b791dcc83e558e07"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e2ef3fa31353b30bda94358fe5205c141289746d"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-401"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels", "id": "2348539", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2348539"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-401", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nnet: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels\nSome lwtunnels have a dst cache for post-transformation dst.\nIf the packet destination did not change we may end up recording\na reference to the lwtunnel in its own cache, and the lwtunnel\nstate will never be freed.\nDiscovered by the ioam6.sh test, kmemleak was recently fixed\nto catch per-cpu memory leaks. I'm not sure if rpl and seg6\ncan actually hit this, but in principle I don't see why not."], "name": "CVE-2025-21768", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Will not fix", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-02-27T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-21768\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-21768\nhttps://lore.kernel.org/linux-cve-announce/2025022605-CVE-2025-21768-512b@gregkh/T"], "threat_severity": "Moderate"}

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