CVE-2021-26339

A bug in AMD CPU’s core logic may allow for an attacker, using specific code from an unprivileged VM, to trigger a CPU core hang resulting in a potential denial of service. AMD believes the specific code includes a specific x86 instruction sequence that would not be generated by compilers.

Published: 2022-05-11 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-26339 is rated Low Risk (28.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.26%). 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-2021-26339

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 0.09% 0.26% +0.17%
2 2025-11-21 0.04% 0.09% +0.05%
3 2025-11-18 — 0.04% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-26339

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-2021-26339

OS Trackers for CVE-2021-26339

vendor priority summary link
suse medium CVE-2021-26339 severity moderate: SUSE including 472 source package names (kernel-firmware, kernel-firmware-20170530-21.34.1, …), 792 product×package rows across 61 product lines (Container rancher/elemental-teal-rt/5.3, Container rancher/elemental-teal-rt/5.4, … (61 product lines)): Fixed 791, Known Not Affected 1. https://www.suse.com/security/cve/CVE-2021-26339/

Affected software / configurations for CVE-2021-26339

Vendor Product Version Raw CPE
amd epyc_7763_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7763_firmware:*:*:*:*:*:*:*:*
amd epyc_7713p_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7713p_firmware:*:*:*:*:*:*:*:*
amd epyc_7713_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7713_firmware:*:*:*:*:*:*:*:*
amd epyc_7663_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7663_firmware:*:*:*:*:*:*:*:*
amd epyc_7643_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7643_firmware:*:*:*:*:*:*:*:*
amd epyc_75f3_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_75f3_firmware:*:*:*:*:*:*:*:*
amd epyc_7543p_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7543p_firmware:*:*:*:*:*:*:*:*
amd epyc_7543_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7543_firmware:*:*:*:*:*:*:*:*
amd epyc_7513_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7513_firmware:*:*:*:*:*:*:*:*
amd epyc_7453_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7453_firmware:*:*:*:*:*:*:*:*
amd epyc_74f3_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_74f3_firmware:*:*:*:*:*:*:*:*
amd epyc_7443p_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7443p_firmware:*:*:*:*:*:*:*:*
amd epyc_7443_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7443_firmware:*:*:*:*:*:*:*:*
amd epyc_7413_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7413_firmware:*:*:*:*:*:*:*:*
amd epyc_73f3_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_73f3_firmware:*:*:*:*:*:*:*:*
amd epyc_7343_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7343_firmware:*:*:*:*:*:*:*:*
amd epyc_7313p_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7313p_firmware:*:*:*:*:*:*:*:*
amd epyc_7313_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7313_firmware:*:*:*:*:*:*:*:*
amd epyc_72f3_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_72f3_firmware:*:*:*:*:*:*:*:*
amd epyc_7773x_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7773x_firmware:*:*:*:*:*:*:*:*
amd epyc_7473x_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7473x_firmware:*:*:*:*:*:*:*:*
amd epyc_7573x_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7573x_firmware:*:*:*:*:*:*:*:*
amd epyc_7373x_firmware < milanpi-sp3_1.0.0.7 cpe:2.3:o:amd:epyc_7373x_firmware:*:*:*:*:*:*:*:*
amd ryzen_7_5700g_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_7_5700g_firmware:*:*:*:*:*:*:*:*
amd ryzen_7_5700ge_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_7_5700ge_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_5700g_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_5_5700g_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_5700ge_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_5_5700ge_firmware:*:*:*:*:*:*:*:*
amd ryzen_3_5300g_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_3_5300g_firmware:*:*:*:*:*:*:*:*
amd ryzen_3_5300ge_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_3_5300ge_firmware:*:*:*:*:*:*:*:*
amd ryzen_7_4700g_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_7_4700g_firmware:*:*:*:*:*:*:*:*
amd ryzen_7_4700ge_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_7_4700ge_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_4600g_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_5_4600g_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_4600ge_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_5_4600ge_firmware:*:*:*:*:*:*:*:*
amd ryzen_3_4300g_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_3_4300g_firmware:*:*:*:*:*:*:*:*
amd ryzen_3_4300ge_firmware < comboam4_v2_pi_1.2.0.6c cpe:2.3:o:amd:ryzen_3_4300ge_firmware:*:*:*:*:*:*:*:*
amd ryzen_threadripper_pro_3945wx_firmware — cpe:2.3:o:amd:ryzen_threadripper_pro_3945wx_firmware:*:*:*:*:*:*:*:*
amd ryzen_threadripper_pro_3955wx_firmware — cpe:2.3:o:amd:ryzen_threadripper_pro_3955wx_firmware:-:*:*:*:*:*:*:*
amd ryzen_threadripper_pro_3975wx_firmware — cpe:2.3:o:amd:ryzen_threadripper_pro_3975wx_firmware:-:*:*:*:*:*:*:*
amd ryzen_threadripper_pro_3995wx_firmware — cpe:2.3:o:amd:ryzen_threadripper_pro_3995wx_firmware:-:*:*:*:*:*:*:*
amd ryzen_threadripper_pro_5945wx_firmware — cpe:2.3:o:amd:ryzen_threadripper_pro_5945wx_firmware:-:*:*:*:*:*:*:*
amd ryzen_threadripper_pro_5955wx_firmware — cpe:2.3:o:amd:ryzen_threadripper_pro_5955wx_firmware:-:*:*:*:*:*:*:*
amd ryzen_threadripper_pro_5965wx_firmware — cpe:2.3:o:amd:ryzen_threadripper_pro_5965wx_firmware:-:*:*:*:*:*:*:*
amd ryzen_threadripper_pro_5975wx_firmware — cpe:2.3:o:amd:ryzen_threadripper_pro_5975wx_firmware:-:*:*:*:*:*:*:*
amd ryzen_threadripper_pro_5995wx_firmware — cpe:2.3:o:amd:ryzen_threadripper_pro_5995wx_firmware:-:*:*:*:*:*:*:*
amd ryzen_3_2200u_firmware — cpe:2.3:o:amd:ryzen_3_2200u_firmware:-:*:*:*:*:*:*:*
amd ryzen_3_2300u_firmware — cpe:2.3:o:amd:ryzen_3_2300u_firmware:-:*:*:*:*:*:*:*
amd ryzen_3_pro_2300u_firmware — cpe:2.3:o:amd:ryzen_3_pro_2300u_firmware:-:*:*:*:*:*:*:*
amd ryzen_5_2500u_firmware — cpe:2.3:o:amd:ryzen_5_2500u_firmware:-:*:*:*:*:*:*:*
amd ryzen_5_pro_2500u_firmware — cpe:2.3:o:amd:ryzen_5_pro_2500u_firmware:-:*:*:*:*:*:*:*
amd ryzen_5_2600h_firmware — cpe:2.3:o:amd:ryzen_5_2600h_firmware:-:*:*:*:*:*:*:*
amd ryzen_7_2700u_firmware — cpe:2.3:o:amd:ryzen_7_2700u_firmware:-:*:*:*:*:*:*:*
amd ryzen_7_pro_2700u_firmware — cpe:2.3:o:amd:ryzen_7_pro_2700u_firmware:-:*:*:*:*:*:*:*
amd ryzen_7_2800h_firmware — cpe:2.3:o:amd:ryzen_7_2800h_firmware:-:*:*:*:*:*:*:*
amd ryzen_3_3300g_firmware — cpe:2.3:o:amd:ryzen_3_3300g_firmware:-:*:*:*:*:*:*:*
amd ryzen_3_3300x_firmware — cpe:2.3:o:amd:ryzen_3_3300x_firmware:-:*:*:*:*:*:*:*
amd ryzen_3_3100_firmware — cpe:2.3:o:amd:ryzen_3_3100_firmware:-:*:*:*:*:*:*:*
amd ryzen_3_pro_3300u_firmware — cpe:2.3:o:amd:ryzen_3_pro_3300u_firmware:-:*:*:*:*:*:*:*
amd ryzen_5_3400g_firmware — cpe:2.3:o:amd:ryzen_5_3400g_firmware:-:*:*:*:*:*:*:*
amd ryzen_5_3450g_firmware — cpe:2.3:o:amd:ryzen_5_3450g_firmware:-:*:*:*:*:*:*:*
amd ryzen_5_3600_firmware — cpe:2.3:o:amd:ryzen_5_3600_firmware:-:*:*:*:*:*:*:*
amd ryzen_5_3600x_firmware — cpe:2.3:o:amd:ryzen_5_3600x_firmware:-:*:*:*:*:*:*:*
amd ryzen_5_pro_3500u_firmware — cpe:2.3:o:amd:ryzen_5_pro_3500u_firmware:-:*:*:*:*:*:*:*
amd ryzen_7_3700x_firmware — cpe:2.3:o:amd:ryzen_7_3700x_firmware:-:*:*:*:*:*:*:*
amd ryzen_7_3800x_firmware — cpe:2.3:o:amd:ryzen_7_3800x_firmware:-:*:*:*:*:*:*:*
amd ryzen_7_pro_3700u_firmware — cpe:2.3:o:amd:ryzen_7_pro_3700u_firmware:-:*:*:*:*:*:*:*
amd ryzen_9_5980hx_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_9_5980hx_firmware:*:*:*:*:*:*:*:*
amd ryzen_9_5980hs_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_9_5980hs_firmware:*:*:*:*:*:*:*:*
amd ryzen_7_5825u_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_7_5825u_firmware:*:*:*:*:*:*:*:*
amd ryzen_9_5900hx_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_9_5900hx_firmware:*:*:*:*:*:*:*:*
amd ryzen_9_5900hs_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_9_5900hs_firmware:*:*:*:*:*:*:*:*
amd ryzen_7_5825c_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_7_5825c_firmware:*:*:*:*:*:*:*:*
amd ryzen_7_5800h_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_7_5800h_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_5625u_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_5_5625u_firmware:*:*:*:*:*:*:*:*
amd ryzen_7_5800hs_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_7_5800hs_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_5625c_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_5_5625c_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_5600h_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_5_5600h_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_5600hs_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_5_5600hs_firmware:*:*:*:*:*:*:*:*
amd ryzen_7_5800u_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_7_5800u_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_5600u_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_5_5600u_firmware:*:*:*:*:*:*:*:*
amd ryzen_5_5560u_firmware < cezannepi-fp6_1.0.0.9a cpe:2.3:o:amd:ryzen_5_5560u_firmware:*:*:*:*:*:*:*:*

References for CVE-2021-26339

cvelogic Threat Intelligence