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Linux KernelOperating system · Linux

CVE-2025-21960

MEDIUM · 5.5 CVSS v3.1 Published 2025-04-01
Fix available
A fix is available. Upgrade to 6.1.132 / 6.6.84 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: eth: bnxt: do not update checksum in bnxt_xdp_build_skb() The bnxt_rx_pkt() updates ip_summed value at the end if checksum offload is enabled. When the XDP-MB program is attached and it returns XDP_PASS, the bnxt_xdp_build_skb() is called to update skb_shared_info. The main purpose of bnxt_xdp_build_skb() is to update skb_shared_info, but it updates ip_summed value too if checksum offload is enabled. This is actually duplicate work. When the bnxt_rx_pkt() updates ip_summed value, it checks if ip_summed is CHECKSUM_NONE or not. It means that ip_summed should be CHECKSUM_NONE at this moment. But ip_summed may already be updated to CHECKSUM_UNNECESSARY in the XDP-MB-PASS path. So the by skb_checksum_none_assert() WARNS about it. This is duplicate work and updating ip_summed in the bnxt_xdp_build_skb() is not needed. Splat looks like: WARNING: CPU: 3 PID: 5782 at ./include/linux/skbuff.h:5155 bnxt_rx_pkt+0x479b/0x7610 [bnxt_en] Modules linked in: bnxt_re bnxt_en rdma_ucm rdma_cm iw_cm ib_cm ib_uverbs veth xt_nat xt_tcpudp xt_conntrack nft_chain_nat xt_MASQUERADE nf_] CPU: 3 UID: 0 PID: 5782 Comm: socat Tainted: G W 6.14.0-rc4+ #27 Tainted: [W]=WARN Hardware name: ASUS System Product Name/PRIME Z690-P D4, BIOS 0603 11/01/2021 RIP: 0010:bnxt_rx_pkt+0x479b/0x7610 [bnxt_en] Code: 54 24 0c 4c 89 f1 4c 89 ff c1 ea 1f ff d3 0f 1f 00 49 89 c6 48 85 c0 0f 84 4c e5 ff ff 48 89 c7 e8 ca 3d a0 c8 e9 8f f4 ff ff <0f> 0b f RSP: 0018:ffff88881ba09928 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 00000000c7590303 RCX: 0000000000000000 RDX: 1ffff1104e7d1610 RSI: 0000000000000001 RDI: ffff8881c91300b8 RBP: ffff88881ba09b28 R08: ffff888273e8b0d0 R09: ffff888273e8b070 R10: ffff888273e8b010 R11: ffff888278b0f000 R12: ffff888273e8b080 R13: ffff8881c9130e00 R14: ffff8881505d3800 R15: ffff888273e8b000 FS: 00007f5a2e7be080(0000) GS:ffff88881ba00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff2e708ff8 CR3: 000000013e3b0000 CR4: 00000000007506f0 PKRU: 55555554 Call Trace: <IRQ> ? __warn+0xcd/0x2f0 ? bnxt_rx_pkt+0x479b/0x7610 ? report_bug+0x326/0x3c0 ? handle_bug+0x53/0xa0 ? exc_invalid_op+0x14/0x50 ? asm_exc_invalid_op+0x16/0x20 ? bnxt_rx_pkt+0x479b/0x7610 ? bnxt_rx_pkt+0x3e41/0x7610 ? __pfx_bnxt_rx_pkt+0x10/0x10 ? napi_complete_done+0x2cf/0x7d0 __bnxt_poll_work+0x4e8/0x1220 ? __pfx___bnxt_poll_work+0x10/0x10 ? __pfx_mark_lock.part.0+0x10/0x10 bnxt_poll_p5+0x36a/0xfa0 ? __pfx_bnxt_poll_p5+0x10/0x10 __napi_poll.constprop.0+0xa0/0x440 net_rx_action+0x899/0xd00 ... Following ping.py patch adds xdp-mb-pass case. so ping.py is going to be able to reproduce this issue.

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

A detailed technical summary for this CVE is being prepared.

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:>= 5.19, < 6.1.132>= 6.2, < 6.6.84>= 6.7, < 6.12.20>= 6.13, < 6.13.8= 6.14

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 6.1.132 / 6.6.84 / 6.12.20 or later
Fixed in 6.1.1326.6.846.12.20
Vendor patch git.kernel.org →
Recommended fix High confidence

Any of: 6.1.132+, 6.6.84+, 6.12.20+, or 6.13.8+ (choose based on your desired stable branch)

  1. Identify the current kernel version using 'uname -r'
  2. Determine which stable branch your current kernel is from (5.19+, 6.1.x, 6.2.x, 6.7.x, or 6.13.x)
  3. Upgrade the Linux kernel to a fixed version: for 6.1.x upgrade to >= 6.1.132; for 6.2.x upgrade to >= 6.6.84; for 6.7.x upgrade to >= 6.12.20; for 6.13.x upgrade to >= 6.13.8
  4. Use your distribution's package manager to install the new kernel (e.g., 'apt-get update && apt-get install linux-image-<version>' for Debian/Ubuntu, or 'yum update kernel' for RHEL/CentOS)
  5. Reboot the system to load the new kernel
  6. Verify the fix is applied by checking the kernel version with 'uname -r' and confirming the bnxt driver no longer produces the WARNING in dmesg'
Caveat Minimal risk - this is a driver bugfix that removes duplicate checksum updates; should not affect normal network operation

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

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

Primary sources

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