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Fencer Vulns
medium 5.6

CVE-2021-26401 json

LFENCE/JMP (mitigation V2-2) may not sufficiently mitigate CVE-2017-5715 on some AMD CPUs.

published 2022-03-11 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-13207

cvss
5.6
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 22%
public exploits
0
none known

Summary

LFENCE/JMP (mitigation V2-2) may not sufficiently mitigate CVE-2017-5715 on some AMD CPUs.

Patch / fix

  • linux Debian 14, Debian 13, Debian 12 5.16.12-1

debian advisories DEBIAN-CVE-2021-26401

  • linux Ubuntu 18.04 LTS 4.15.0-177.186
  • linux Ubuntu 20.04 LTS 5.4.0-110.124
  • linux-aws Ubuntu 18.04 LTS 4.15.0-1128.137
  • linux-aws Ubuntu 20.04 LTS 5.4.0-1073.78
  • linux-gcp Ubuntu 20.04 LTS 5.4.0-1073.78
  • linux-gke Ubuntu 20.04 LTS 5.4.0-1071.76
  • linux-ibm Ubuntu 20.04 LTS 5.4.0-1021.23
  • linux-iot Ubuntu 20.04 LTS 5.4.0-1004.6

ubuntu advisories UBUNTU-CVE-2021-26401

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel RHEL 8 4.18.0-372.9.1.el8
  • perf RHEL 8 4.18.0-372.9.1.el8
  • bpftool RHEL 8 4.18.0-372.9.1.el8
  • kernel-core RHEL 8 4.18.0-372.9.1.el8
  • kernel-tools RHEL 8 4.18.0-372.9.1.el8
  • python3-perf RHEL 8 4.18.0-372.9.1.el8
  • kernel-modules RHEL 8 4.18.0-372.9.1.el8
  • kernel-zfcpdump RHEL 8 4.18.0-372.9.1.el8

red hat advisories RHSA-2022:1988RHSA-2023:0400RHSA-2023:0399RHSA-2022:1975RHSA-2023:0187

  • xen SLES for SAP 12 SP3, SLES 12 SP3-LTSS, SLES 12 SP3-BCL +3 more 4.9.4_28-3.103.1
  • xen SLES 12 SP2-BCL 4.7.6_22-43.88.1
  • xen SLES for SAP 15, SLE High Performance Computing 15-LTSS, SLE High Performance Computing 15-ESPOS 4.10.4_34-150000.3.74.1
  • xen SLES for SAP 15 SP2, SLES 15 SP2-LTSS, SLES 15 SP2-BCL +8 more 4.13.4_08-150200.3.50.1
  • xen SLES for SAP 12 SP4, SLES 12 SP4-LTSS, OpenStack Cloud Crowbar 9 +1 more 4.11.4_28-2.73.1
  • xen SLE Module for Server Applications 15 SP3, SLE Module for Basesystem 15 SP3, SLE Micro 5.1 4.14.4_02-150300.3.21.1
  • xen SLES for SAP 12 SP5, SLES 12 SP5, SLE Software Development Kit 12 SP5 4.12.4_20-3.61.1
  • xen SLES for SAP 15 SP1, SLES 15 SP1-LTSS, SLES 15 SP1-BCL +3 more 4.12.4_20-3.63.1

suse advisories SUSE-SU-2022:1408-1SUSE-SU-2022:1375-1SUSE-SU-2022:1359-1SUSE-SU-2022:1300-1SUSE-SU-2022:1285-1SUSE-SU-2022:0940-1

  • xen openSUSE Leap 15.3 4.14.4_02-150300.3.21.1

opensuse advisories openSUSE-SU-2022:0940-1

  • kernel AlmaLinux 8 4.18.0-372.9.1.el8
  • perf AlmaLinux 8 4.18.0-372.9.1.el8
  • bpftool AlmaLinux 8 4.18.0-372.9.1.el8
  • kernel-core AlmaLinux 8 4.18.0-372.9.1.el8
  • kernel-tools AlmaLinux 8 4.18.0-372.9.1.el8
  • python3-perf AlmaLinux 8 4.18.0-372.9.1.el8
  • kernel-modules AlmaLinux 8 4.18.0-372.9.1.el8
  • kernel-debug-core AlmaLinux 8 4.18.0-372.9.1.el8

almalinux advisories ALSA-2022:1988

  • kernel Rocky Linux 8 4.18.0-372.9.1.el8
  • kernel-rt Rocky Linux 8 4.18.0-372.9.1.rt7.166.el8

rocky linux advisories RLSA-2022:1988RLSA-2022:1975

  • xen Alpine 3.15, Alpine 3.14 4.15.2-r2

alpine advisories ALPINE-CVE-2021-26401

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-26401 updated cvss 4.7

hw: cpu: LFENCE/JMP Mitigation Update for CVE-2017-5715

  • Red Hat Enterprise Linux BaseOS (v. 8) perf 4.18.0-372.9.1.el8, kernel 4.18.0-372.9.1.el8, bpftool 4.18.0-372.9.1.el8, kernel-core 4.18.0-372.9.1.el8, kernel-tools 4.18.0-372.9.1.el8, python3-perf 4.18.0-372.9.1.el8, +15 more
    fixed: vendor fix “AMD recommends mitigation that uses generic retpoline.” RHSA-2022:1988
  • Red Hat Enterprise Linux Client (v. 7) perf 3.10.0-1160.83.1.el7, kernel 3.10.0-1160.83.1.el7, bpftool 3.10.0-1160.83.1.el7, python-perf 3.10.0-1160.83.1.el7, kernel-tools 3.10.0-1160.83.1.el7, kernel-tools-libs 3.10.0-1160.83.1.el7, +2 more Red Hat Enterprise Linux Client Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1160.83.1.el7 Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1160.83.1.el7
    fixed: vendor fix “AMD recommends mitigation that uses generic retpoline.” RHSA-2023:0399
  • Red Hat Enterprise Linux CRB (v. 8) kernel-debuginfo-common-x86_64 4.18.0-372.9.1.el8, kernel-debuginfo-common-aarch64 4.18.0-372.9.1.el8, kernel-debuginfo-common-ppc64le 4.18.0-372.9.1.el8
    fixed: vendor fix “AMD recommends mitigation that uses generic retpoline.” RHSA-2022:1988
  • Red Hat Enterprise Linux for Real Time (v. 7) kernel-rt 3.10.0-1160.83.1.rt56.1228.el7, kernel-rt-trace 3.10.0-1160.83.1.rt56.1228.el7, kernel-rt-debuginfo-common-x86_64 3.10.0-1160.83.1.rt56.1228.el7 Red Hat Enterprise Linux for Real Time for NFV (v. 7) kernel-rt 3.10.0-1160.83.1.rt56.1228.el7, kernel-rt-kvm 3.10.0-1160.83.1.rt56.1228.el7, kernel-rt-trace 3.10.0-1160.83.1.rt56.1228.el7, kernel-rt-debug-kvm 3.10.0-1160.83.1.rt56.1228.el7, kernel-rt-trace-kvm 3.10.0-1160.83.1.rt56.1228.el7, kernel-rt-debuginfo-common-x86_64 3.10.0-1160.83.1.rt56.1228.el7
    fixed: vendor fix “AMD recommends mitigation that uses generic retpoline.” RHSA-2023:0400
  • Red Hat Enterprise Linux NFV (v. 8) kernel-rt 4.18.0-372.9.1.rt7.166.el8, kernel-rt-kvm 4.18.0-372.9.1.rt7.166.el8, kernel-rt-core 4.18.0-372.9.1.rt7.166.el8, kernel-rt-modules 4.18.0-372.9.1.rt7.166.el8, kernel-rt-debug-kvm 4.18.0-372.9.1.rt7.166.el8, kernel-rt-debug-core 4.18.0-372.9.1.rt7.166.el8, +4 more Red Hat Enterprise Linux RT (v. 8) kernel-rt 4.18.0-372.9.1.rt7.166.el8, kernel-rt-core 4.18.0-372.9.1.rt7.166.el8, kernel-rt-modules 4.18.0-372.9.1.rt7.166.el8, kernel-rt-debug-core 4.18.0-372.9.1.rt7.166.el8, kernel-rt-debug-modules 4.18.0-372.9.1.rt7.166.el8, kernel-rt-modules-extra 4.18.0-372.9.1.rt7.166.el8, +2 more
    fixed: vendor fix “AMD recommends mitigation that uses generic retpoline.” RHSA-2022:1975
  • Red Hat Enterprise Linux Server (v. 6 ELS) perf 2.6.32-754.49.1.el6, kernel 2.6.32-754.49.1.el6, kernel-kdump 2.6.32-754.49.1.el6, kernel-firmware 2.6.32-754.49.1.el6, kernel-abi-whitelists 2.6.32-754.49.1.el6, kernel-debuginfo-common-i686 2.6.32-754.49.1.el6, +2 more
    fixed: vendor fix “AMD recommends mitigation that uses generic retpoline.” RHSA-2023:0187
  • Red Hat Enterprise Linux Server (v. 7) perf 3.10.0-1160.83.1.el7, kernel 3.10.0-1160.83.1.el7, bpftool 3.10.0-1160.83.1.el7, python-perf 3.10.0-1160.83.1.el7, kernel-kdump 3.10.0-1160.83.1.el7, kernel-tools 3.10.0-1160.83.1.el7, +7 more
    fixed: vendor fix “AMD recommends mitigation that uses generic retpoline.” RHSA-2023:0399
  • Red Hat Enterprise Linux Server Optional (v. 6 ELS) python-perf 2.6.32-754.49.1.el6, kernel-debuginfo-common-i686 2.6.32-754.49.1.el6, kernel-debuginfo-common-s390x 2.6.32-754.49.1.el6, kernel-debuginfo-common-x86_64 2.6.32-754.49.1.el6
    fixed: vendor fix “AMD recommends mitigation that uses generic retpoline.” RHSA-2023:0187
show 2 more
  • Red Hat Enterprise Linux Server Optional (v. 7) kernel-debuginfo-common-ppc64 3.10.0-1160.83.1.el7, kernel-debuginfo-common-x86_64 3.10.0-1160.83.1.el7, kernel-debuginfo-common-ppc64le 3.10.0-1160.83.1.el7 Red Hat Enterprise Linux Workstation (v. 7) perf 3.10.0-1160.83.1.el7, kernel 3.10.0-1160.83.1.el7, bpftool 3.10.0-1160.83.1.el7, python-perf 3.10.0-1160.83.1.el7, kernel-tools 3.10.0-1160.83.1.el7, kernel-tools-libs 3.10.0-1160.83.1.el7, +2 more Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1160.83.1.el7
    fixed: vendor fix “AMD recommends mitigation that uses generic retpoline.” RHSA-2023:0399
  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux Server (v. 6 ELS) kernel-headers 2.6.32-754.49.1.el6
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-25-105-08 updated cvss 5.6

ABB M2M Gateway

  • ABB M2M Gateway >=4.1.2, <=5.0.3, >=5.0.1, <=5.0.3
    affected: mitigation

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-23-075-01 updated cvss 5.6

Siemens SCALANCE, RUGGEDCOM Third-Party

  • Siemens RUGGEDCOM RM1224 LTE(4G) EU (6GK6108-4AM00-2BA2) <V7.2 Siemens RUGGEDCOM RM1224 LTE(4G) NAM (6GK6108-4AM00-2DA2) <V7.2 Siemens SCALANCE M804PB (6GK5804-0AP00-2AA2) <V7.2 Siemens SCALANCE M812-1 ADSL-Router (Annex A) (6GK5812-1AA00-2AA2) <V7.2 Siemens SCALANCE M812-1 ADSL-Router (Annex B) (6GK5812-1BA00-2AA2) <V7.2 Siemens SCALANCE M816-1 ADSL-Router (Annex A) (6GK5816-1AA00-2AA2) <V7.2
    +14 more products
    Siemens SCALANCE M816-1 ADSL-Router (Annex B) (6GK5816-1BA00-2AA2) <V7.2 Siemens SCALANCE M826-2 SHDSL-Router (6GK5826-2AB00-2AB2) <V7.2 Siemens SCALANCE M874-2 (6GK5874-2AA00-2AA2) <V7.2 Siemens SCALANCE M874-3 (6GK5874-3AA00-2AA2) <V7.2 Siemens SCALANCE M876-3 (EVDO) (6GK5876-3AA02-2BA2) <V7.2 Siemens SCALANCE M876-3 (ROK) (6GK5876-3AA02-2EA2) <V7.2 Siemens SCALANCE M876-4 (6GK5876-4AA10-2BA2) <V7.2 Siemens SCALANCE M876-4 (EU) (6GK5876-4AA00-2BA2) <V7.2 Siemens SCALANCE M876-4 (NAM) (6GK5876-4AA00-2DA2) <V7.2 Siemens SCALANCE MUM853-1 (EU) (6GK5853-2EA00-2DA1) <V7.2 Siemens SCALANCE MUM856-1 (EU) (6GK5856-2EA00-3DA1) <V7.2 Siemens SCALANCE MUM856-1 (RoW) (6GK5856-2EA00-3AA1) <V7.2 Siemens SCALANCE S615 (6GK5615-0AA00-2AA2) <V7.2 Siemens SCALANCE S615 EEC (6GK5615-0AA01-2AA2) <V7.2
    affected: fixed in V7.2 support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

Exploit prediction

0.29% chance of exploitation in the next 30 days, higher than 22% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 5.6 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
NVD 2.0 1.9 AV:L/AC:M/Au:N/C:P/I:N/A:N

Affected products

  • AMD AMD Processors

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.