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

> A memory leak in the Linux kernel's JFFS2 filesystem allows attackers to cause a denial of service via resource exhaustion during mount operations.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 Feb 2025
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-49276, GHSA-jg9p-qrj8-5jw6, UBUNTU-CVE-2022-49276

## What is CVE-2022-49276?

CVE-2022-49276 is a medium-severity memory corruption vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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)

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2022-49276?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49276?

Apply the vendor's patch.

## Is CVE-2022-49276 being exploited?

There is no known exploitation of CVE-2022-49276 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-49276 and fix it if it is affected.

What it is: CVE-2022-49276 is a medium-severity memory corruption vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-49276 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2022-49276/ (Markdown: https://insights.sbomify.com/CVE-2022-49276/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49276
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49276
- OSV: https://osv.dev/vulnerability/CVE-2022-49276

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49276/
Summaries are generated and may contain mistakes; the official description above is the record.
