Linux KernelOperating system · Linux

CVE-2022-49096

MEDIUM · 5.5 CVSS v3.1 Published 2025-02-26
Fix available
A fix is available. Upgrade to 5.15.34 / 5.16.20 or later.
See remediation →
57/100
Remediation priority · Elevated
Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In the Linux kernel, the following vulnerability has been resolved: net: sfc: add missing xdp queue reinitialization After rx/tx ring buffer size is changed, kernel panic occurs when it acts XDP_TX or XDP_REDIRECT. When tx/rx ring buffer size is changed(ethtool -G), sfc driver reallocates and reinitializes rx and tx queues and their buffer (tx_queue->buffer). But it misses reinitializing xdp queues(efx->xdp_tx_queues). So, while it is acting XDP_TX or XDP_REDIRECT, it uses the uninitialized tx_queue->buffer. A new function efx_set_xdp_channels() is separated from efx_set_channels() to handle only xdp queues. Splat looks like: BUG: kernel NULL pointer dereference, address: 000000000000002a #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#4] PREEMPT SMP NOPTI RIP: 0010:efx_tx_map_chunk+0x54/0x90 [sfc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G D 5.17.0+ #55 e8beeee8289528f11357029357cf Code: 48 8b 8d a8 01 00 00 48 8d 14 52 4c 8d 2c d0 44 89 e0 48 85 c9 74 0e 44 89 e2 4c 89 f6 48 80 RSP: 0018:ffff92f121e45c60 EFLAGS: 00010297 RIP: 0010:efx_tx_map_chunk+0x54/0x90 [sfc] RAX: 0000000000000040 RBX: ffff92ea506895c0 RCX: ffffffffc0330870 RDX: 0000000000000001 RSI: 00000001139b10ce RDI: ffff92ea506895c0 RBP: ffffffffc0358a80 R08: 00000001139b110d R09: 0000000000000000 R10: 0000000000000001 R11: ffff92ea414c0088 R12: 0000000000000040 R13: 0000000000000018 R14: 00000001139b10ce R15: ffff92ea506895c0 FS: 0000000000000000(0000) GS:ffff92f121ec0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Code: 48 8b 8d a8 01 00 00 48 8d 14 52 4c 8d 2c d0 44 89 e0 48 85 c9 74 0e 44 89 e2 4c 89 f6 48 80 CR2: 000000000000002a CR3: 00000003e6810004 CR4: 00000000007706e0 RSP: 0018:ffff92f121e85c60 EFLAGS: 00010297 PKRU: 55555554 RAX: 0000000000000040 RBX: ffff92ea50689700 RCX: ffffffffc0330870 RDX: 0000000000000001 RSI: 00000001145a90ce RDI: ffff92ea50689700 RBP: ffffffffc0358a80 R08: 00000001145a910d R09: 0000000000000000 R10: 0000000000000001 R11: ffff92ea414c0088 R12: 0000000000000040 R13: 0000000000000018 R14: 00000001145a90ce R15: ffff92ea50689700 FS: 0000000000000000(0000) GS:ffff92f121e80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000002a CR3: 00000003e6810005 CR4: 00000000007706e0 PKRU: 55555554 Call Trace: <IRQ> efx_xdp_tx_buffers+0x12b/0x3d0 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5] __efx_rx_packet+0x5c3/0x930 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5] efx_rx_packet+0x28c/0x2e0 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5] efx_ef10_ev_process+0x5f8/0xf40 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5] ? enqueue_task_fair+0x95/0x550 efx_poll+0xc4/0x360 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis
How this class of weakness works · CWE-476

The code follows a pointer that is null, crashing the process. An attacker who can reliably trigger it turns the crash into a denial of service. The fix is checking for null before use and handling the failure path gracefully.

General guidance for the null pointer dereference class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux KernelOperating system
Affected:>= 5.5, < 5.15.34>= 5.16, < 5.16.20>= 5.17, < 5.17.3= 5.18

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

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

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 5.15.34 / 5.16.20 / 5.17.3 or later
Fixed in 5.15.345.16.205.17.3
Vendor patch git.kernel.org →
Recommended fix High confidence

Kernel 5.15.34+, 5.16.20+, 5.17.3+, or 5.18+ (depending on which branch you are on)

  1. Identify the current running kernel version using `uname -r`
  2. Check if the kernel version falls within any of the affected ranges: 5.5 <= version < 5.15.34, 5.16.0-5.16.19, 5.17.0-5.17.2, or exactly 5.18
  3. If affected, schedule a maintenance window for kernel upgrade
  4. Upgrade to a patched kernel version: 5.15.34 or later, 5.16.20 or later, 5.17.3 or later, or 5.18.1 or later
  5. Reboot the system to load the patched kernel
  6. Verify the fix by running `modinfo sfc` or checking the kernel release notes for the commit 059a47f1da93811d37533556d67e72f2261b1127
Caveat Standard kernel upgrade risks apply; ensure compatibility with local modules and configuration before upgrading

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $2,850. Get the upgrade done

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2022-49096 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2022-49096 in production — separate from our analysis above.

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What this is

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