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TI-2021-08858 Aliases CVE-2021-27363GHSA-ghrr-3969-mcfp

An issue was discovered in the Linux kernel through 5.11.3.

Priority LOW 22Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · None · Low
Fix status
Partial Red Hat: 38 fixed, 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

An issue was discovered in the Linux kernel through 5.11.3. A kernel pointer leak can be used to determine the address of the iscsi_transport structure. When an iSCSI transport is registered with the iSCSI subsystem, the transport's handle is available to unprivileged users via the sysfs file system, at /sys/class/iscsi_transport/$TRANSPORT_NAME/handle. When read, the show_transport_handle function (in drivers/scsi/scsi_transport_iscsi.c) is called, which leaks the handle. This handle is actually the pointer to an iscsi_transport struct in the kernel module's global variables.

Why it matters now

EPSS 0.00711 53rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 12 advisoriesRed Hat: 38 fixed, 2 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*up to 5.11.3VulnerableLinux
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:o:netapp:solidfire_baseboard_management_controller_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions up to 5.11.3 Vulnerable ·Linux
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
  • cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:o:netapp:solidfire_baseboard_management_controller_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp

Remediation

Red Hat 12 advisories

  • RHSA-2021:1531 Released 2021-05-11 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux ComputeNode EUS (v. 7.7) bpftool-3.10.0-1062.49.1.el7, kernel-3.10.0-1062.49.1.el7, kernel-abi-whitelists-3.10.0-1062.49.1.el7 +8
    • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.7) kernel-tools-libs-devel-3.10.0-1062.49.1.el7
    • Red Hat Enterprise Linux Server EUS (v. 7.7) bpftool-3.10.0-1062.49.1.el7, kernel-3.10.0-1062.49.1.el7, kernel-abi-whitelists-3.10.0-1062.49.1.el7 +11
    • Red Hat Enterprise Linux Server Optional EUS (v. 7.7) kernel-debug-devel-3.10.0-1062.49.1.el7, kernel-tools-libs-devel-3.10.0-1062.49.1.el7
  • RHSA-2021:1376 Released 2021-04-27 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux ComputeNode EUS (v. 7.6) bpftool-3.10.0-957.72.1.el7, kernel-3.10.0-957.72.1.el7, kernel-abi-whitelists-3.10.0-957.72.1.el7 +8
    • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6) kernel-tools-libs-devel-3.10.0-957.72.1.el7
    • Red Hat Enterprise Linux Server EUS (v. 7.6) bpftool-3.10.0-957.72.1.el7, kernel-3.10.0-957.72.1.el7, kernel-abi-whitelists-3.10.0-957.72.1.el7 +11
    • Red Hat Enterprise Linux Server Optional EUS (v. 7.6) kernel-debug-devel-3.10.0-957.72.1.el7, kernel-tools-libs-devel-3.10.0-957.72.1.el7
    • Red Hat Virtualization 4.2 Hypervisor for RHEL 7.6 EUS kernel-devel-3.10.0-957.72.1.el7, perf-3.10.0-957.72.1.el7, python-perf-3.10.0-957.72.1.el7
  • RHSA-2021:1373 Released 2021-04-27 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux Server AUS (v. 7.3) kernel-3.10.0-514.88.1.el7, kernel-abi-whitelists-3.10.0-514.88.1.el7, kernel-debug-3.10.0-514.88.1.el7 +7
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.3) kernel-tools-libs-devel-3.10.0-514.88.1.el7
Show 9 more Red Hat advisories
  • RHSA-2021:1289 Released 2021-04-20 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux Server AUS (v. 7.2) kernel-3.10.0-327.96.1.el7, kernel-abi-whitelists-3.10.0-327.96.1.el7, kernel-debug-3.10.0-327.96.1.el7 +7
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.2) kernel-tools-libs-devel-3.10.0-327.96.1.el7
  • RHSA-2021:1272 Released 2021-04-20 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder EUS (v. 8.2) kernel-tools-libs-devel-4.18.0-193.51.1.el8_2
    • Red Hat Enterprise Linux BaseOS EUS (v. 8.2) bpftool-4.18.0-193.51.1.el8_2, kernel-4.18.0-193.51.1.el8_2, kernel-abi-whitelists-4.18.0-193.51.1.el8_2 +19
  • RHSA-2021:1279 Released 2021-04-20 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux Real Time EUS (v. 8.2) kernel-rt-4.18.0-193.51.1.rt13.101.el8_2, kernel-rt-core-4.18.0-193.51.1.rt13.101.el8_2, kernel-rt-debug-4.18.0-193.51.1.rt13.101.el8_2 +7
    • Red Hat Enterprise Linux Real Time for NFV EUS (v. 8.2) kernel-rt-4.18.0-193.51.1.rt13.101.el8_2, kernel-rt-core-4.18.0-193.51.1.rt13.101.el8_2, kernel-rt-debug-4.18.0-193.51.1.rt13.101.el8_2 +9
  • RHSA-2021:1267 Released 2021-04-20 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux Server AUS (v. 7.4) kernel-3.10.0-693.84.1.el7, kernel-abi-whitelists-3.10.0-693.84.1.el7, kernel-debug-3.10.0-693.84.1.el7 +7
    • Red Hat Enterprise Linux Server E4S (v. 7.4) kernel-3.10.0-693.84.1.el7, kernel-abi-whitelists-3.10.0-693.84.1.el7, kernel-bootwrapper-3.10.0-693.84.1.el7 +8
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.4) kernel-tools-libs-devel-3.10.0-693.84.1.el7
    • Red Hat Enterprise Linux Server Optional E4S (v. 7.4) kernel-debug-devel-3.10.0-693.84.1.el7, kernel-tools-libs-devel-3.10.0-693.84.1.el7
    • Red Hat Enterprise Linux Server Optional TUS (v. 7.4) kernel-tools-libs-devel-3.10.0-693.84.1.el7
    • Red Hat Enterprise Linux Server TUS (v. 7.4) kernel-3.10.0-693.84.1.el7, kernel-abi-whitelists-3.10.0-693.84.1.el7, kernel-debug-3.10.0-693.84.1.el7 +7
  • RHSA-2021:1171 Released 2021-04-13 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat CodeReady Linux Builder EUS (v. 8.1) kernel-tools-libs-devel-4.18.0-147.44.1.el8_1
    • Red Hat Enterprise Linux BaseOS EUS (v. 8.1) bpftool-4.18.0-147.44.1.el8_1, kernel-4.18.0-147.44.1.el8_1, kernel-abi-whitelists-4.18.0-147.44.1.el8_1 +19
  • RHSA-2021:1071 Released 2021-04-08 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux Client (v. 7) bpftool-3.10.0-1160.24.1.el7, kernel-3.10.0-1160.24.1.el7, kernel-abi-whitelists-3.10.0-1160.24.1.el7 +8
    • Red Hat Enterprise Linux Client Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.24.1.el7
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.24.1.el7
    • Red Hat Enterprise Linux Server (v. 7) bpftool-3.10.0-1160.24.1.el7, kernel-3.10.0-1160.24.1.el7, kernel-abi-whitelists-3.10.0-1160.24.1.el7 +11
    • Red Hat Enterprise Linux Server Optional (v. 7) kernel-debug-devel-3.10.0-1160.24.1.el7, kernel-tools-libs-devel-3.10.0-1160.24.1.el7
    • Red Hat Enterprise Linux Workstation (v. 7) bpftool-3.10.0-1160.24.1.el7, kernel-3.10.0-1160.24.1.el7, kernel-abi-whitelists-3.10.0-1160.24.1.el7 +8
    • Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.24.1.el7
  • RHSA-2021:1093 Released 2021-04-06 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder (v. 8) kernel-tools-libs-devel-4.18.0-240.22.1.el8_3
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-240.22.1.el8_3, kernel-4.18.0-240.22.1.el8_3, kernel-abi-whitelists-4.18.0-240.22.1.el8_3 +19
  • RHSA-2021:1081 Released 2021-04-06 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux Real Time (v. 8) kernel-rt-4.18.0-240.22.1.rt7.77.el8_3, kernel-rt-core-4.18.0-240.22.1.rt7.77.el8_3, kernel-rt-debug-4.18.0-240.22.1.rt7.77.el8_3 +7
    • Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt-4.18.0-240.22.1.rt7.77.el8_3, kernel-rt-core-4.18.0-240.22.1.rt7.77.el8_3, kernel-rt-debug-4.18.0-240.22.1.rt7.77.el8_3 +9
  • RHSA-2021:1070 Released 2021-04-06 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux for Real Time (v. 7) kernel-rt-3.10.0-1160.24.1.rt56.1161.el7, kernel-rt-debug-3.10.0-1160.24.1.rt56.1161.el7, kernel-rt-debug-devel-3.10.0-1160.24.1.rt56.1161.el7 +4
    • Red Hat Enterprise Linux for Real Time for NFV (v. 7) kernel-rt-3.10.0-1160.24.1.rt56.1161.el7, kernel-rt-debug-3.10.0-1160.24.1.rt56.1161.el7, kernel-rt-debug-devel-3.10.0-1160.24.1.rt56.1161.el7 +7

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2021:1093
Red Hat CodeReady Linux Builder EUS (v. 8.1)Fixed RHSA-2021:1171
Red Hat CodeReady Linux Builder EUS (v. 8.2)Fixed RHSA-2021:1272
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2021:1093
Red Hat Enterprise Linux BaseOS EUS (v. 8.1)Fixed RHSA-2021:1171
Red Hat Enterprise Linux BaseOS EUS (v. 8.2)Fixed RHSA-2021:1272
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2021:1071
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2021:1071
Red Hat Enterprise Linux ComputeNode EUS (v. 7.6)Fixed RHSA-2021:1376
Red Hat Enterprise Linux ComputeNode EUS (v. 7.7)Fixed RHSA-2021:1531
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2021:1071
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6)Fixed RHSA-2021:1376
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.7)Fixed RHSA-2021:1531
Red Hat Enterprise Linux Real Time (v. 8)Fixed RHSA-2021:1081
Red Hat Enterprise Linux Real Time EUS (v. 8.2)Fixed RHSA-2021:1279
Red Hat Enterprise Linux Real Time for NFV (v. 8)Fixed RHSA-2021:1081
Red Hat Enterprise Linux Real Time for NFV EUS (v. 8.2)Fixed RHSA-2021:1279
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2021:1071
Red Hat Enterprise Linux Server AUS (v. 7.2)Fixed RHSA-2021:1289
Red Hat Enterprise Linux Server AUS (v. 7.3)Fixed RHSA-2021:1373
Red Hat Enterprise Linux Server AUS (v. 7.4)Fixed RHSA-2021:1267
Red Hat Enterprise Linux Server E4S (v. 7.4)Fixed RHSA-2021:1267
Red Hat Enterprise Linux Server EUS (v. 7.6)Fixed RHSA-2021:1376
Red Hat Enterprise Linux Server EUS (v. 7.7)Fixed RHSA-2021:1531
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2021:1071
Red Hat Enterprise Linux Server Optional AUS (v. 7.2)Fixed RHSA-2021:1289
Red Hat Enterprise Linux Server Optional AUS (v. 7.3)Fixed RHSA-2021:1373
Red Hat Enterprise Linux Server Optional AUS (v. 7.4)Fixed RHSA-2021:1267
Red Hat Enterprise Linux Server Optional E4S (v. 7.4)Fixed RHSA-2021:1267
Red Hat Enterprise Linux Server Optional EUS (v. 7.6)Fixed RHSA-2021:1376
Red Hat Enterprise Linux Server Optional EUS (v. 7.7)Fixed RHSA-2021:1531
Red Hat Enterprise Linux Server Optional TUS (v. 7.4)Fixed RHSA-2021:1267
Red Hat Enterprise Linux Server TUS (v. 7.4)Fixed RHSA-2021:1267
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2021:1071
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2021:1071
Red Hat Enterprise Linux for Real Time (v. 7)Fixed RHSA-2021:1070
Red Hat Enterprise Linux for Real Time for NFV (v. 7)Fixed RHSA-2021:1070
Red Hat Virtualization 4.2 Hypervisor for RHEL 7.6 EUSFixed RHSA-2021:1376
Not affected: 1 product
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-27363
  2. 2026-10-03 Alias added: GHSA-ghrr-3969-mcfp

References

Exploit 1

Patch 2

Advisory 5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences