CVE-2021-26342
Last modified
CVE-2021-26342 is a low-severity vulnerability rated 3.3/10 on the CVSS scale. In SEV guest VMs, the CPU may fail to flush the Translation Lookaside Buffer (TLB) following a particular sequence of operations that includes creation of a new virtual machine control block (VMCB). The failure to flush the TLB may cause the microcode to use stale TLB translations which may allow for disclosure of SEV guest memory contents. EPSS estimates a 0.21% chance of exploitation in the next 30 days.
Description
In SEV guest VMs, the CPU may fail to flush the Translation Lookaside Buffer (TLB) following a particular sequence of operations that includes creation of a new virtual machine control block (VMCB). The failure to flush the TLB may cause the microcode to use stale TLB translations which may allow for disclosure of SEV guest memory contents. Users of SEV-ES/SEV-SNP guest VMs are not impacted by this vulnerability.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Amd | Epyc 7763 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7713p Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7713 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7663 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7643 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 75f3 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7543p Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7543 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7513 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7453 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 74f3 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7443p Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7443 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7413 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 73f3 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7343 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7313p Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7313 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 72f3 Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7773x Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7473x Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7573x Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7373x Firmware | < milanpi-sp3_1.0.0.7 |
| Amd | Epyc 7001 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7251 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7261 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7281 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7301 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7351 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7351p Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7371 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7401 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7401p Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7451 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7501 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7551 Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7551p Firmware | < naplespi-sp3_1.0.0.h |
| Amd | Epyc 7601 Firmware | < naplespi-sp3_1.0.0.h |
References
Timeline
- Published
- Last Modified
- Status
- Modified
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