NVD / CVE Program· CNA Linux

CVE-2022-49840: bpf, test_run: Fix alignment problem in bpf_prog_test_run_skb()

Noroxi assessment

Priority: Monitor (action score 31/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.22% (FIRST EPSS).
Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: Linux Linux 047824a730699c6c66df43306b80f700c9dfc2fd, 1b597f2d6a55e9f549989913860ad5170da04964, 730fb1ef974a13915bc7651364d8b3318891cd70.

Low priority for now. Upgrade to Linux Linux 047824a730699c6c66df43306b80f700c9dfc2fd, 1b597f2d6a55e9f549989913860ad5170da04964, 730fb1ef974a13915bc7651364d8b3318891cd70 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: bpf, test_run: Fix alignment problem in bpf_prog_test_run_skb() We got a syzkaller problem because of aarch64 alignment fault if KFENCE enabled. When the size from user bpf program is an odd number, like 399, 407, etc, it will cause the struct skb_shared_info's unaligned access. As seen below: BUG: KFENCE: use-after-free read in __skb_clone+0x23c/0x2a0 net/core/skbuff.c:1032 Use-after-free read at 0xffff6254fffac077 (in kfence-#213): __lse_atomic_add arch/arm64/include/asm/atomic_lse.h:26 [inline] arch_atomic_add arch/arm64/include/asm/atomic.h:28 [inline] arch_atomic_inc include/linux/atomic-arch-fallback.h:270 [inline] atomic_inc include/asm-generic/atomic-instrumented.h:241 [inline] __skb_clone+0x23c/0x2a0 net/core/skbuff.c:1032 skb_clone+0xf4/0x214 net/core/skbuff.c:1481 ____bpf_clone_redirect net/core/filter.c:2433 [inline] bpf_clone_redirect+0x78/0x1c0 net/core/filter.c:2420 bpf_prog_d3839dd9068ceb51+0x80/0x330 bpf_dispatcher_nop_func include/linux/bpf.h:728 [inline] bpf_test_run+0x3c0/0x6c0 net/bpf/test_run.c:53 bpf_prog_test_run_skb+0x638/0xa7c net/bpf/test_run.c:594 bpf_prog_test_run kernel/bpf/syscall.c:3148 [inline] __do_sys_bpf kernel/bpf/syscall.c:4441 [inline] __se_sys_bpf+0xad0/0x1634 kernel/bpf/syscall.c:4381 kfence-#213: 0xffff6254fffac000-0xffff6254fffac196, size=407, cache=kmalloc-512 allocated by task 15074 on cpu 0 at 1342.585390s: kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:675 [inline] bpf_test_init.isra.0+0xac/0x290 net/bpf/test_run.c:191 bpf_prog_test_run_skb+0x11c/0xa7c net/bpf/test_run.c:512 bpf_prog_test_run kernel/bpf/syscall.c:3148 [inline] __do_sys_bpf kernel/bpf/syscall.c:4441 [inline] __se_sys_bpf+0xad0/0x1634 kernel/bpf/syscall.c:4381 __arm64_sys_bpf+0x50/0x60 kernel/bpf/syscall.c:4381 To fix the problem, we adjust @size so that (@size + @hearoom) is a multiple of SMP_CACHE_BYTES. So we make sure the struct skb_shared_info is aligned to a cache line.

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

BDU:2025-10252

Published: May 1, 2025
Updated: Jun 17, 2026
EPSS: 0.2% · 12th percentile
CWE: CWE-416

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.2%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
linux	linux kernel	cpe:2.3:o:linux:linux_kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

linux linux kernel4.12 and later · before 4.14.300
linux linux kernel4.15 and later · before 4.19.267
linux linux kernel4.20 and later · before 5.4.225
linux linux kernel5.5 and later · before 5.10.156
linux linux kernel5.11 and later · before 5.15.80
linux linux kernel5.16 and later · before 6.0.10
linux linux kernel6.1

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

Linux Linux
- 4.12affected
- 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 and later · before 047824a730699c6c66df43306b80f700c9dfc2fdaffected · git
- 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 and later · before 730fb1ef974a13915bc7651364d8b3318891cd70affected · git
- 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 and later · before 7a704dbfd3735304e261f2787c52fbc7c3884736affected · git
- 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 and later · before e60f37a1d379c821c17b08f366412dce9ef3d99faffected · git
- 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 and later · before eaa8edd86514afac9deb9bf9a5053e74f37edf40affected · git
- 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 and later · before 1b597f2d6a55e9f549989913860ad5170da04964affected · git
- 1cf1cae963c2e6032aebe1637e995bc2f5d330f4 and later · before d3fd203f36d46aa29600a72d57a1b61af80e4a25affected · git
- before 4.12not affected · semver
- 4.14.300 and later · up to and including 4.14.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Debian:12	linux	before 6.0.10-1	6.0.10-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
90Now
CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
89Now
CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
85Now

Published before and after this one in the same product

← EarlierCVE-2022-49838May 1, 2025 · sctp: clear out_curr if all frag chunks of current msg are pruned
22Monitor
← EarlierCVE-2022-49839May 1, 2025 · scsi: scsi_transport_sas: Fix error handling in sas_phy_add()
22Monitor
Later →CVE-2022-49841May 1, 2025 · serial: imx: Add missing .thaw_noirq hook
22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Linux Linux	047824a730699c6c66df43306b80f700c9dfc2fd	Vendor (CNA)
Linux Linux	1b597f2d6a55e9f549989913860ad5170da04964	Vendor (CNA)
Linux Linux	730fb1ef974a13915bc7651364d8b3318891cd70	Vendor (CNA)
Linux Linux	7a704dbfd3735304e261f2787c52fbc7c3884736	Vendor (CNA)
Linux Linux	d3fd203f36d46aa29600a72d57a1b61af80e4a25	Vendor (CNA)
Linux Linux	e60f37a1d379c821c17b08f366412dce9ef3d99f	Vendor (CNA)
Linux Linux	eaa8edd86514afac9deb9bf9a5053e74f37edf40	Vendor (CNA)
debian:linux	6.0.10-1 · Debian:12	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-416 · Use After Free

CVSS vector

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

nvd-primary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1free(dev->buf);
2/* ... another thread is still running ... */
3process(dev->buf);

Fixed

1lock(&dev->lock);
2free(dev->buf);
3dev->buf = NULL;
4unlock(&dev->lock);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

Fix✗ → ✓Sep 28, 2026, 10:09 PM UTC

For records you follow, these changes also arrive as notifications. →

References

git.kernel.org/stable/c/047824a730699c6c66df43306b80f700c9dfc2fd

Show all references (6 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records