CVE-2022-49276 [Medium] | Information Disclosure in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: jffs2: fix memory leak in jffs2_scan_medium If an error is returned in jffs2_scan_eraseblock() and some memory has been added to the jffs2_summary *s, we can observe the following kmemleak report: -------------------------------------------- unreferenced object 0xffff88812b889c40 (size 64): comm "mount", pid 692, jiffies 4294838325 (age 34.288s) hex dump (first 32 bytes): 40 48 b5 14 81 88 ff ff 01 e0 31 00 00 00 50 00 @H........1...P. 00 00 01 00 00 00 01 00 00 00 02 00 00 00 09 08 ................ backtrace: [<ffffffffae93a3a3>] __kmalloc+0x613/0x910 [<ffffffffaf423b9c>] jffs2_sum_add_dirent_mem+0x5c/0xa0 [<ffffffffb0f3afa8>] jffs2_scan_medium.cold+0x36e5/0x4794 [<ffffffffb0f3dbe1>] jffs2_do_mount_fs.cold+0xa7/0x2267 [<ffffffffaf40acf3>] jffs2_do_fill_super+0x383/0xc30 [<ffffffffaf40c00a>] jffs2_fill_super+0x2ea/0x4c0 [<ffffffffb0315d64>] mtd_get_sb+0x254/0x400 [<ffffffffb0315f5f>] mtd_get_sb_by_nr+0x4f/0xd0 [<ffffffffb0316478>] get_tree_mtd+0x498/0x840 [<ffffffffaf40bd15>] jffs2_get_tree+0x25/0x30 [<ffffffffae9f358d>] vfs_get_tree+0x8d/0x2e0 [<ffffffffaea7a98f>] path_mount+0x50f/0x1e50 [<ffffffffaea7c3d7>] do_mount+0x107/0x130 [<ffffffffaea7c5c5>] __se_sys_mount+0x1c5/0x2f0 [<ffffffffaea7c917>] __x64_sys_mount+0xc7/0x160 [<ffffffffb10142f5>] do_syscall_64+0x45/0x70 unreferenced object 0xffff888114b54840 (size 32): comm "mount", pid 692, jiffies 4294838325 (age 34.288s) hex dump (first 32 bytes): c0 75 b5 14 81 88 ff ff 02 e0 02 00 00 00 02 00 .u.............. 00 00 84 00 00 00 44 00 00 00 6b 6b 6b 6b 6b a5 ......D...kkkkk. backtrace: [<ffffffffae93be24>] kmem_cache_alloc_trace+0x584/0x880 [<ffffffffaf423b04>] jffs2_sum_add_inode_mem+0x54/0x90 [<ffffffffb0f3bd44>] jffs2_scan_medium.cold+0x4481/0x4794 [...] unreferenced object 0xffff888114b57280 (size 32): comm "mount", pid 692, jiffies 4294838393 (age 34.357s) hex dump (first 32 bytes): 10 d5 6c 11 81 88 ff ff 08 e0 05 00 00 00 01 00 ..l............. 00 00 38 02 00 00 28 00 00 00 6b 6b 6b 6b 6b a5 ..8...(...kkkkk. backtrace: [<ffffffffae93be24>] kmem_cache_alloc_trace+0x584/0x880 [<ffffffffaf423c34>] jffs2_sum_add_xattr_mem+0x54/0x90 [<ffffffffb0f3a24f>] jffs2_scan_medium.cold+0x298c/0x4794 [...] unreferenced object 0xffff8881116cd510 (size 16): comm "mount", pid 692, jiffies 4294838395 (age 34.355s) hex dump (first 16 bytes): 00 00 00 00 00 00 00 00 09 e0 60 02 00 00 6b a5 ..........`...k. backtrace: [<ffffffffae93be24>] kmem_cache_alloc_trace+0x584/0x880 [<ffffffffaf423cc4>] jffs2_sum_add_xref_mem+0x54/0x90 [<ffffffffb0f3b2e3>] jffs2_scan_medium.cold+0x3a20/0x4794 [...] -------------------------------------------- Therefore, we should call jffs2_sum_reset_collected(s) on exit to release the memory added in s. In addition, a new tag "out_buf" is added to prevent the NULL pointer reference caused by s being NULL. (thanks to Zhang Yi for this analysis)

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-04-15	0.06%	0.02%	-0.04%
2	2025-03-17	0.04%	0.06%	+0.02%
3	2025-02-27	—	0.04%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-04-15

0.06%

0.02%

-0.04%

2025-03-17

0.04%

0.06%

+0.02%

2025-02-27

—

0.04%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
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]
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	134c704f-9b21-4f2e-91b3-4a467353bcc0

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

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]

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

134c704f-9b21-4f2e-91b3-4a467353bcc0

OS Trackers for CVE-2022-49276

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2022-49276 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2022-49276
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2022-49276
`suse`	medium	—	https://www.suse.com/security/cve/CVE-2022-49276/
`ubuntu`	medium	CVE-2022-49276 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, ignored 149, released 145, not-affected 107, needed 5.	https://ubuntu.com/security/CVE-2022-49276

Affected software / configurations for CVE-2022-49276

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 2.6.15, < 4.9.311	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 4.10, < 4.14.276	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 4.15, < 4.19.238	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 4.20, < 5.4.189	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.5, < 5.10.110	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.11, < 5.15.33	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.16, < 5.16.19	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.17, < 5.17.2	cpe:2.3:o:linux:linux_kernel::::::::

References for CVE-2022-49276

URL	Tags
https://git.kernel.org/stable/c/455f4a23490bfcbedc8e5c245c463a59b19e5ddd	Patch
https://git.kernel.org/stable/c/51dbb5e36d59f62e34d462b801c1068248149cfe	Patch
https://git.kernel.org/stable/c/52ba0ab4f0a606f02a6163493378989faa1ec10a	Patch
https://git.kernel.org/stable/c/82462324bf35b6b553400af1c1aa265069cee28f	Patch
https://git.kernel.org/stable/c/9b0c69182f09b70779817af4dcf89780955d5c4c	Patch
https://git.kernel.org/stable/c/9cdd3128874f5fe759e2c4e1360ab7fb96a8d1df	Patch
https://git.kernel.org/stable/c/b26bbc0c122cad038831f226a4cb4de702225e16	Patch
https://git.kernel.org/stable/c/b36bccb04e14cc0c1e2d0e92d477fe220314fad6	Patch
https://git.kernel.org/stable/c/e711913463af916d777a4873068f415f1fe2ad33	Patch

URL

CVE-2022-49276 | jffs2: fix memory leak in jffs2_scan_medium

Exploit prediction scoring system (EPSS) score for CVE-2022-49276

Common vulnerability scoring system (CVSS) metrics for CVE-2022-49276

Weakness enumeration for CVE-2022-49276

OS Trackers for CVE-2022-49276

Affected software / configurations for CVE-2022-49276

References for CVE-2022-49276