CVE-2021-45485

In the IPv6 implementation in the Linux kernel before 5.13.3, net/ipv6/output_core.c has an information leak because of certain use of a hash table which, although big, doesn't properly consider that IPv6-based attackers can typically choose among many IPv6 source addresses.

Published: 2021-12-25 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-45485 is rated Moderate Risk (63.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 3.62%). EPSS rose +2.52% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-45485

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 1.10% 3.62% +2.52%
2 2026-06-11 0.87% 1.10% +0.23%
3 2026-04-20 — 0.87% —

Full EPSS history (25 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-45485

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2021-45485

OS Trackers for CVE-2021-45485

vendor priority summary link
debian not yet assigned CVE-2021-45485 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-45485
redhat medium — https://access.redhat.com/security/cve/CVE-2021-45485
suse low CVE-2021-45485 severity low: SUSE including 470 source package names (amazon/suse-sles-15-sp1-chost-byos-v20210304-hvm-ssd-x86_64, amazon/suse-sles-15-sp1-chost-byos-v20220127-hvm-ssd-x86_64, …), 850 product×package rows across 114 product lines (Container suse/sle-micro-rancher/5.2, HPE Helion OpenStack 8, … (114 product lines)): Fixed 655, Known Affected 172, Known Not Affected 23. https://www.suse.com/security/cve/CVE-2021-45485/
ubuntu medium CVE-2021-45485 medium priority: Ubuntu including 167 source packages (linux, linux-allwinner, …), 2101 status rows across 15 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1627, not-affected 209, released 206, ignored 58, needed 1. https://ubuntu.com/security/CVE-2021-45485

Affected software / configurations for CVE-2021-45485

Vendor Product Version Raw CPE
linux linux_kernel < 5.13.3 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
netapp e-series_santricity_os_controller — cpe:2.3:a:netapp:e-series_santricity_os_controller:-:*:*:*:*:*:*:*
netapp solidfire\,_enterprise_sds_\&_hci_storage_node — cpe:2.3:a:netapp:solidfire\,_enterprise_sds_\&_hci_storage_node:-:*:*:*:*:*:*:*
netapp solidfire_\&_hci_management_node — cpe:2.3:a:netapp:solidfire_\&_hci_management_node:-:*:*:*:*:*:*:*
netapp brocade_fabric_operating_system_firmware — cpe:2.3:o:netapp:brocade_fabric_operating_system_firmware:-:*:*:*:*:*:*:*
oracle communications_cloud_native_core_binding_support_function 22.1.3 cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:22.1.3:*:*:*:*:*:*:*
oracle communications_cloud_native_core_network_exposure_function 22.1.1 cpe:2.3:a:oracle:communications_cloud_native_core_network_exposure_function:22.1.1:*:*:*:*:*:*:*
oracle communications_cloud_native_core_policy 22.2.0 cpe:2.3:a:oracle:communications_cloud_native_core_policy:22.2.0:*:*:*:*:*:*:*
netapp all_flash_fabric-attached_storage_8300_firmware — cpe:2.3:o:netapp:all_flash_fabric-attached_storage_8300_firmware:-:*:*:*:*:*:*:*
netapp fabric-attached_storage_8300_firmware — cpe:2.3:o:netapp:fabric-attached_storage_8300_firmware:-:*:*:*:*:*:*:*
netapp all_flash_fabric-attached_storage_8700_firmware — cpe:2.3:o:netapp:all_flash_fabric-attached_storage_8700_firmware:-:*:*:*:*:*:*:*
netapp fabric-attached_storage_8700_firmware — cpe:2.3:o:netapp:fabric-attached_storage_8700_firmware:-:*:*:*:*:*:*:*
netapp aff_a400_firmware — cpe:2.3:o:netapp:aff_a400_firmware:-:*:*:*:*:*:*:*
netapp fabric-attached_storage_a400_firmware — cpe:2.3:o:netapp:fabric-attached_storage_a400_firmware:-:*:*:*:*:*:*:*
netapp hci_compute_node_firmware — cpe:2.3:o:netapp:hci_compute_node_firmware:-:*:*:*:*:*:*:*
netapp h300e_firmware — cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:*
netapp h300s_firmware — cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*
netapp h410c_firmware — cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:*
netapp h410s_firmware — cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*
netapp h500e_firmware — cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:*
netapp h500s_firmware — cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*
netapp h610c_firmware — cpe:2.3:o:netapp:h610c_firmware:-:*:*:*:*:*:*:*
netapp h610s_firmware — cpe:2.3:o:netapp:h610s_firmware:-:*:*:*:*:*:*:*
netapp h615c_firmware — cpe:2.3:o:netapp:h615c_firmware:-:*:*:*:*:*:*:*
netapp h700e_firmware — cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:*
netapp h700s_firmware — cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*

References for CVE-2021-45485

cvelogic Threat Intelligence