CVE-2026-43020

high

Published 2026-05-01 · Modified 2026-05-28

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CVSS v3

7.8

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS v4 NEW

—

not yet in upstream

VIR risk

7.8

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: validate LTK enc_size on load Load Long Term Keys stores the user-provided enc_size and later uses it to size fixed-size stack operations when replying to LE LTK requests. An enc_size larger than the 16-byte key buffer can therefore overflow the reply stack buffer. Reject oversized enc_size values while validating the management LTK record so invalid keys never reach the stored key state.

Predictions

Exploit likelihood

75%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

Mitigation details

Source: Red Hat Errata — Red Hat Inc. · View original ↗ · Open-Errata-API

Description kernel: Bluetooth: MGMT: validate LTK enc_size on load CVSS v3: 7.3 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H) Errata / fixed releases ProductPackageAdvisoryReleased Red Hat Enterprise Linux 10kernel-0:6.12.0-211.18.1.el10_2RHSA-2026:215572026-05-28T00:00:00Z Red Hat Enterprise Linux 9kernel-0:5.14.0-687.12.1.el9_8RHSA-2026:215562026-05-28T00:00:00Z Red Hat Enterprise Linux…

Description

kernel: Bluetooth: MGMT: validate LTK enc_size on load

CVSS v3: 7.3 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H)

Errata / fixed releases

Product	Package	Advisory	Released
Red Hat Enterprise Linux 10	`kernel-0:6.12.0-211.18.1.el10_2`	RHSA-2026:21557	2026-05-28T00:00:00Z
Red Hat Enterprise Linux 9	`kernel-0:5.14.0-687.12.1.el9_8`	RHSA-2026:21556	2026-05-28T00:00:00Z
Red Hat Enterprise Linux 9	`kernel-0:5.14.0-687.12.1.el9_8`	RHSA-2026:21556	2026-05-28T00:00:00Z

Package state

Product	Package	State
Red Hat Enterprise Linux 6	`kernel`	Not affected
Red Hat Enterprise Linux 7	`kernel`	Affected
Red Hat Enterprise Linux 7	`kernel-rt`	Affected
Red Hat Enterprise Linux 8	`kernel`	Affected
Red Hat Enterprise Linux 8	`kernel-rt`	Affected
Red Hat Enterprise Linux 9	`kernel-rt`	Affected

Apply commands

bash fix

Apply RHSA-2026:21557 for Red Hat Enterprise Linux 10

yum update -y kernel
# or:
dnf upgrade -y kernel

Affected

Vendor	Product	Version
redhat	Red Hat Enterprise Linux 6	`Not affected`
redhat	Red Hat Enterprise Linux 7	`Affected`
redhat	Red Hat Enterprise Linux 7	`Affected`
redhat	Red Hat Enterprise Linux 8	`Affected`
redhat	Red Hat Enterprise Linux 8	`Affected`
redhat	Red Hat Enterprise Linux 9	`Affected`

OS impact

OS	Version	Status	Fixed in
sles		affected
rhel	9	fixed
debian	bookworm	fixed	`6.1.170-1`
debian	forky	fixed	`6.19.12-1`
debian	sid	fixed	`6.19.12-1`
debian	trixie	fixed	`6.12.85-1`
debian	bullseye	fixed	`6.1.170-1~deb11u1`
linux-kernel		affected	`5.10.253`
linux-kernel	7.0	affected
almalinux	8	fixed	`kernel-doc-4.18.0-553.126.1.el8_10.noarch.rpm`

References

CWEs

CWE-787

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.