CVE-2020-7463

In FreeBSD 12.1-STABLE before r364644, 11.4-STABLE before r364651, 12.1-RELEASE before p9, 11.4-RELEASE before p3, and 11.3-RELEASE before p13, improper handling in the kernel causes a use-after-free bug by sending large user messages from multiple threads on the same SCTP socket. The use-after-free situation may result in unintended kernel behaviour including a kernel panic.

Published: 2021-03-26 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-7463 is rated Low Risk (33.4/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.40%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2020-7463

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 0.05% 0.40% +0.35%
2 2025-04-28 0.08% 0.05% -0.03%
3 2025-03-17 — 0.08% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-7463

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
A normal user session is enough; they don’t have to be admin.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]
4.9 2.0 MEDIUM
AV:L/AC:L/Au:N/C:N/I:N/A:C Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:C)
Complete availability impact.
 3.9 6.9 [email protected]

Weakness enumeration for CVE-2020-7463

Affected software / configurations for CVE-2020-7463

Vendor Product Version Raw CPE
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:-:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p1:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p10:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p11:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p12:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p2:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p3:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p4:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p5:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p6:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p7:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p8:*:*:*:*:*:*
freebsd freebsd 11.3 cpe:2.3:o:freebsd:freebsd:11.3:p9:*:*:*:*:*:*
freebsd freebsd 11.4 cpe:2.3:o:freebsd:freebsd:11.4:-:*:*:*:*:*:*
freebsd freebsd 11.4 cpe:2.3:o:freebsd:freebsd:11.4:p1:*:*:*:*:*:*
freebsd freebsd 11.4 cpe:2.3:o:freebsd:freebsd:11.4:p2:*:*:*:*:*:*
freebsd freebsd 12.1 cpe:2.3:o:freebsd:freebsd:12.1:-:*:*:*:*:*:*
freebsd freebsd 12.1 cpe:2.3:o:freebsd:freebsd:12.1:p1:*:*:*:*:*:*
freebsd freebsd 12.1 cpe:2.3:o:freebsd:freebsd:12.1:p2:*:*:*:*:*:*
freebsd freebsd 12.1 cpe:2.3:o:freebsd:freebsd:12.1:p3:*:*:*:*:*:*
freebsd freebsd 12.1 cpe:2.3:o:freebsd:freebsd:12.1:p4:*:*:*:*:*:*
freebsd freebsd 12.1 cpe:2.3:o:freebsd:freebsd:12.1:p5:*:*:*:*:*:*
freebsd freebsd 12.1 cpe:2.3:o:freebsd:freebsd:12.1:p6:*:*:*:*:*:*
freebsd freebsd 12.1 cpe:2.3:o:freebsd:freebsd:12.1:p7:*:*:*:*:*:*
freebsd freebsd 12.1 cpe:2.3:o:freebsd:freebsd:12.1:p8:*:*:*:*:*:*
freebsd freebsd 12.2 cpe:2.3:o:freebsd:freebsd:12.2:-:*:*:*:*:*:*
apple icloud < 12.3 cpe:2.3:a:apple:icloud:*:*:*:*:*:windows:*:*
apple itunes < 12.11.3 cpe:2.3:a:apple:itunes:*:*:*:*:*:windows:*:*
apple safari < 14.1 cpe:2.3:a:apple:safari:*:*:*:*:*:*:*:*
apple ipados < 14.5 cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple iphone_os < 14.5 cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple macos >= 11.0, < 11.3 cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
apple tvos < 14.5 cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
apple watchos < 7.4 cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

References for CVE-2020-7463

URL Tags
http://seclists.org/fulldisclosure/2021/Apr/49 Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Apr/50 Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Apr/57 Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Apr/58 Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Apr/59 Mailing List Third Party Advisory
https://security.FreeBSD.org/advisories/FreeBSD-SA-20:25.sctp.asc Vendor Advisory
https://support.apple.com/kb/HT212317 Third Party Advisory
https://support.apple.com/kb/HT212318 Third Party Advisory
https://support.apple.com/kb/HT212319 Third Party Advisory
https://support.apple.com/kb/HT212321 Third Party Advisory
https://support.apple.com/kb/HT212323 Third Party Advisory
https://support.apple.com/kb/HT212324 Third Party Advisory
https://support.apple.com/kb/HT212325 Third Party Advisory
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