CVE-2026-22991 [High] | Security Vulnerability in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: libceph: make free_choose_arg_map() resilient to partial allocation free_choose_arg_map() may dereference a NULL pointer if its caller fails after a partial allocation. For example, in decode_choose_args(), if allocation of arg_map->args fails, execution jumps to the fail label and free_choose_arg_map() is called. Since arg_map->size is updated to a non-zero value before memory allocation, free_choose_arg_map() will iterate over arg_map->args and dereference a NULL pointer. To prevent this potential NULL pointer dereference and make free_choose_arg_map() more resilient, add checks for pointers before iterating.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.02%	0.40%	+0.37%
2	2026-01-24	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.02%

0.40%

+0.37%

2026-01-24

—

0.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.5	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. 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:N) No account or special rights needed—anonymous or random user is enough. 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.	3.9	3.6	416baaa9-dc9f-4396-8d5f-8c081fb06d67
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]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.5

3.1

HIGH

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

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:N): No account or special rights needed—anonymous or random user is enough.
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.

3.9

3.6

416baaa9-dc9f-4396-8d5f-8c081fb06d67

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]

OS Trackers for CVE-2026-22991

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2026-22991 not yet assigned priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6.	https://security-tracker.debian.org/tracker/CVE-2026-22991
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2026-22991
`suse`	medium	CVE-2026-22991 severity moderate: SUSE including 386 source package names (13.2-9.1:libsqlite3-0-3.49.1-1.1, 2.1.3-6.115:kernel-default-base-6.4.0-39.1.21.16, …), 579 product×package rows across 68 product lines (Container suse/sl-micro/6.0/baremetal-os-container, Container suse/sl-micro/6.0/base-os-container, … (68 product lines)): Fixed 310, Known Affected 231, First Fixed 25, Known Not Affected 13.	https://www.suse.com/security/cve/CVE-2026-22991/
`ubuntu`	medium	CVE-2026-22991 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1256 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): DNE 871, ignored 173, released 114, needed 92, pending 6.	https://ubuntu.com/security/CVE-2026-22991

Affected software / configurations for CVE-2026-22991

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 4.13, < 5.10.248	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.11, < 5.15.198	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.16, < 6.1.161	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.2, < 6.6.121	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.7, < 6.12.66	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.13, < 6.18.6	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc1::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc2::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc3::::::
linux	linux_kernel	6.19	cpe:2.3:o:linux:linux_kernel:6.19:rc4::::::

References for CVE-2026-22991

URL	Tags
https://git.kernel.org/stable/c/8081faaf089db5280c3be820948469f7c58ef8dd	Patch
https://git.kernel.org/stable/c/851241d3f78a5505224dc21c03d8692f530256b4	Patch
https://git.kernel.org/stable/c/9b3730dabcf3764bfe3ff07caf55e641a0b45234	Patch
https://git.kernel.org/stable/c/c4c2152a858c0ce4d2bff6ca8c1d5b0ef9f2cbdf	Patch
https://git.kernel.org/stable/c/e3fe30e57649c551757a02e1cad073c47e1e075e	Patch
https://git.kernel.org/stable/c/ec1850f663da64842614c86b20fe734be070c2ba	Patch
https://git.kernel.org/stable/c/f21c3fdb96833aac2f533506899fe38c19cf49d5	Patch

URL

CVE-2026-22991 | libceph: make free_choose_arg_map() resilient to partial allocation

Exploit prediction scoring system (EPSS) score for CVE-2026-22991

Common vulnerability scoring system (CVSS) metrics for CVE-2026-22991

Weakness enumeration for CVE-2026-22991

OS Trackers for CVE-2026-22991

Affected software / configurations for CVE-2026-22991

References for CVE-2026-22991