{"cve":"CVE-2021-20322","nvd":{"published":"2022-02-18T18:15:09.013","modified":"2026-07-30T19:33:26.700","status":"Analyzed","description":"A flaw in the processing of received ICMP errors (ICMP fragment needed and ICMP redirect) in the Linux kernel functionality was found to allow the ability to quickly scan open UDP ports. This flaw allows an off-path remote user to effectively bypass the source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source port randomization are indirectly affected as well.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","score":7.4},"cwes":["CWE-330"],"references":["https://bugzilla.redhat.com/show_bug.cgi?id=2014230","https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v5.15-rc6&id=4785305c05b25a242e5314cc821f54ade4c18810","https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v5.15-rc6&id=6457378fe796815c973f631a1904e147d6ee33b1","https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/ipv4/route.c?h=v5.15-rc6&id=67d6d681e15b578c1725bad8ad079e05d1c48a8e","https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/ipv6/route.c?h=v5.15-rc6&id=a00df2caffed3883c341d5685f830434312e4a43"],"products":["debian:debian_linux","fedoraproject:fedora","linux:linux_kernel","netapp:active_iq_unified_manager","netapp:aff_a700s_firmware","netapp:aff_baseboard_management_controller_firmware","netapp:e-series_santricity_os_controller","netapp:fas_baseboard_management_controller_firmware","netapp:h300e_firmware","netapp:h300s_firmware","netapp:h410s_firmware","netapp:h500e_firmware","netapp:h500s_firmware","netapp:h700e_firmware","netapp:h700s_firmware","netapp:hci_compute_node_firmware","netapp:solidfire\\,_enterprise_sds_\\&_hci_storage_node","netapp:solidfire_\\&_hci_management_node","oracle:communications_cloud_native_core_binding_support_function","oracle:communications_cloud_native_core_network_exposure_function","oracle:communications_cloud_native_core_policy"],"source":"nvd","synced_at":"2026-10-19T21:28:04.509275555+00:00"},"epss":{"cve":"CVE-2021-20322","score":0.06902,"percentile":0.94084,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}