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Fencer Vulns
high 7.5

CVE-2025-21961 json

eth: bnxt: fix truesize for mb-xdp-pass case

published 2025-04-01 19 mo ago modified 2026-10-30 10 d ago also EUVD-2025-9359

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 48%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

eth: bnxt: fix truesize for mb-xdp-pass case

When mb-xdp is set and return is XDP_PASS, packet is converted from xdp_buff to sk_buff with xdp_update_skb_shared_info() in bnxt_xdp_build_skb(). bnxt_xdp_build_skb() passes incorrect truesize argument to xdp_update_skb_shared_info(). The truesize is calculated as BNXT_RX_PAGE_SIZE * sinfo->nr_frags but the skb_shared_info was wiped by napi_build_skb() before. So it stores sinfo->nr_frags before bnxt_xdp_build_skb() and use it instead of getting skb_shared_info from xdp_get_shared_info_from_buff().

Splat looks like: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 0 at net/core/skbuff.c:6072 skb_try_coalesce+0x504/0x590 Modules linked in: xt_nat xt_tcpudp veth af_packet xt_conntrack nft_chain_nat xt_MASQUERADE nf_conntrack_netlink xfrm_user xt_addrtype nft_coms CPU: 2 UID: 0 PID: 0 Comm: swapper/2 Not tainted 6.14.0-rc2+ #3 RIP: 0010:skb_try_coalesce+0x504/0x590 Code: 4b fd ff ff 49 8b 34 24 40 80 e6 40 0f 84 3d fd ff ff 49 8b 74 24 48 40 f6 c6 01 0f 84 2e fd ff ff 48 8d 4e ff e9 25 fd ff ff <0f> 0b e99 RSP: 0018:ffffb62c4120caa8 EFLAGS: 00010287 RAX: 0000000000000003 RBX: ffffb62c4120cb14 RCX: 0000000000000ec0 RDX: 0000000000001000 RSI: ffffa06e5d7dc000 RDI: 0000000000000003 RBP: ffffa06e5d7ddec0 R08: ffffa06e6120a800 R09: ffffa06e7a119900 R10: 0000000000002310 R11: ffffa06e5d7dcec0 R12: ffffe4360575f740 R13: ffffe43600000000 R14: 0000000000000002 R15: 0000000000000002 FS: 0000000000000000(0000) GS:ffffa0755f700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f147b76b0f8 CR3: 00000001615d4000 CR4: 00000000007506f0 PKRU: 55555554 Call Trace: <IRQ> ? __warn+0x84/0x130 ? skb_try_coalesce+0x504/0x590 ? report_bug+0x18a/0x1a0 ? handle_bug+0x53/0x90 ? exc_invalid_op+0x14/0x70 ? asm_exc_invalid_op+0x16/0x20 ? skb_try_coalesce+0x504/0x590 inet_frag_reasm_finish+0x11f/0x2e0 ip_defrag+0x37a/0x900 ip_local_deliver+0x51/0x120 ip_sublist_rcv_finish+0x64/0x70 ip_sublist_rcv+0x179/0x210 ip_list_rcv+0xf9/0x130

How to reproduce: <Node A> ip link set $interface1 xdp obj xdp_pass.o ip link set $interface1 mtu 9000 up ip a a 10.0.0.1/24 dev $interface1 <Node B> ip link set $interfac2 mtu 9000 up ip a a 10.0.0.2/24 dev $interface2 ping 10.0.0.1 -s 65000

Following ping.py patch adds xdp-mb-pass case. so ping.py is going to be able to reproduce this issue.

Patch / fix

  • Linux Linux 6.1.191, 6.6.160, 6.12.20, 6.13.8, 6.14
  • linux Debian 14, Debian 13 6.12.20-1

debian advisories DEBIAN-CVE-2025-21961

  • linux Ubuntu 24.04 LTS 6.8.0-84.84
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1039.41
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1040.42
  • linux-gke Ubuntu 24.04 LTS 6.8.0-1036.40
  • linux-ibm Ubuntu 24.04 LTS 6.8.0-1037.37
  • linux-azure Ubuntu 24.04 LTS 6.8.0-1038.44
  • linux-gkeop Ubuntu 24.04 LTS 6.8.0-1023.25
  • linux-raspi Ubuntu 24.04 LTS 6.8.0-1039.43

ubuntu advisories UBUNTU-CVE-2025-21961

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel RHEL 10.0 6.12.0-55.19.1.el10_0
  • rv RHEL 10.0 6.12.0-55.19.1.el10_0
  • perf RHEL 10.0 6.12.0-55.19.1.el10_0
  • rtla RHEL 10.0 6.12.0-55.19.1.el10_0
  • libperf RHEL 10.0 6.12.0-55.19.1.el10_0
  • kernel-rt RHEL 10.0 6.12.0-55.19.1.el10_0
  • kernel-64k RHEL 10.0 6.12.0-55.19.1.el10_0
  • kernel-core RHEL 10.0 6.12.0-55.19.1.el10_0

red hat advisories RHSA-2025:9896RHSA-2025:9080

  • kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.20.3.1
  • kernel-syms-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.20.3.1
  • kernel-source-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.20.3.1
  • kernel-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.39.1
  • kernel-syms-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.39.1
  • kernel-rt_debug Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.39.1
  • kernel-source-rt Real Time Module 15 SP6, openSUSE Leap 15.6 6.4.0-150600.10.39.1
  • kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.3.1

suse advisories SUSE-SU-2025:01967-1SUSE-SU-2025:01964-1SUSE-SU-2025:01951-1SUSE-SU-2025:01919-1SUSE-SU-2025:01707-1SUSE-SU-2025:01614-1

  • kernel-abi-stablelists AlmaLinux 10 6.12.0-55.19.1.el10_0
  • kernel AlmaLinux 9 5.14.0-570.22.1.el9_6
  • rv AlmaLinux 9 5.14.0-570.22.1.el9_6
  • perf AlmaLinux 9 5.14.0-570.22.1.el9_6
  • rtla AlmaLinux 9 5.14.0-570.22.1.el9_6
  • libperf AlmaLinux 9 5.14.0-570.22.1.el9_6
  • kernel-rt AlmaLinux 9 5.14.0-570.22.1.el9_6
  • kernel-64k AlmaLinux 9 5.14.0-570.22.1.el9_6

almalinux advisories ALSA-2025:9896ALSA-2025:9080

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2025-21961 updated cvss 4.7

kernel: eth: bnxt: fix truesize for mb-xdp-pass case

  • Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more
    affected: workaround, no fix planned “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.”
  • Red Hat Enterprise Linux AppStream (v. 9) rv 5.14.0-570.22.1.el9_6, perf 5.14.0-570.22.1.el9_6, rtla 5.14.0-570.22.1.el9_6, python3-perf 5.14.0-570.22.1.el9_6, kernel-devel-matched 5.14.0-570.22.1.el9_6, kernel-64k-devel-matched 5.14.0-570.22.1.el9_6, +7 more
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9080
  • Red Hat Enterprise Linux AppStream (v. 10) rv 6.12.0-55.19.1.el10_0, perf 6.12.0-55.19.1.el10_0, rtla 6.12.0-55.19.1.el10_0, python3-perf 6.12.0-55.19.1.el10_0, kernel-devel-matched 6.12.0-55.19.1.el10_0, kernel-64k-devel-matched 6.12.0-55.19.1.el10_0, +7 more
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9896
  • Red Hat Enterprise Linux BaseOS (v. 9) kernel 5.14.0-570.22.1.el9_6, kernel-64k 5.14.0-570.22.1.el9_6, kernel-core 5.14.0-570.22.1.el9_6, kernel-tools 5.14.0-570.22.1.el9_6, kernel-modules 5.14.0-570.22.1.el9_6, kernel-64k-core 5.14.0-570.22.1.el9_6, +27 more
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9080
  • Red Hat Enterprise Linux BaseOS (v. 10) kernel 6.12.0-55.19.1.el10_0, kernel-64k 6.12.0-55.19.1.el10_0, kernel-core 6.12.0-55.19.1.el10_0, kernel-tools 6.12.0-55.19.1.el10_0, kernel-modules 6.12.0-55.19.1.el10_0, kernel-64k-core 6.12.0-55.19.1.el10_0, +27 more
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9896
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) libperf 5.14.0-570.22.1.el9_6, kernel-debuginfo-common-s390x 5.14.0-570.22.1.el9_6, kernel-debuginfo-common-x86_64 5.14.0-570.22.1.el9_6, kernel-debuginfo-common-aarch64 5.14.0-570.22.1.el9_6, kernel-debuginfo-common-ppc64le 5.14.0-570.22.1.el9_6
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9080
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) libperf 6.12.0-55.19.1.el10_0, kernel-debuginfo-common-s390x 6.12.0-55.19.1.el10_0, kernel-debuginfo-common-x86_64 6.12.0-55.19.1.el10_0, kernel-debuginfo-common-aarch64 6.12.0-55.19.1.el10_0, kernel-debuginfo-common-ppc64le 6.12.0-55.19.1.el10_0
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9896
  • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt 5.14.0-570.22.1.el9_6, kernel-rt-64k 5.14.0-570.22.1.el9_6, kernel-rt-core 5.14.0-570.22.1.el9_6, kernel-rt-modules 5.14.0-570.22.1.el9_6, kernel-rt-64k-core 5.14.0-570.22.1.el9_6, kernel-rt-debug-core 5.14.0-570.22.1.el9_6, +14 more
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9080
show 4 more
  • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt 6.12.0-55.19.1.el10_0, kernel-rt-64k 6.12.0-55.19.1.el10_0, kernel-rt-core 6.12.0-55.19.1.el10_0, kernel-rt-modules 6.12.0-55.19.1.el10_0, kernel-rt-64k-core 6.12.0-55.19.1.el10_0, kernel-rt-debug-core 6.12.0-55.19.1.el10_0, +14 more
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9896
  • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt 5.14.0-570.22.1.el9_6, kernel-rt-kvm 5.14.0-570.22.1.el9_6, kernel-rt-core 5.14.0-570.22.1.el9_6, kernel-rt-modules 5.14.0-570.22.1.el9_6, kernel-rt-debug-kvm 5.14.0-570.22.1.el9_6, kernel-rt-debug-core 5.14.0-570.22.1.el9_6, +6 more
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9080
  • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt 6.12.0-55.19.1.el10_0, kernel-rt-kvm 6.12.0-55.19.1.el10_0, kernel-rt-core 6.12.0-55.19.1.el10_0, kernel-rt-modules 6.12.0-55.19.1.el10_0, kernel-rt-debug-kvm 6.12.0-55.19.1.el10_0, kernel-rt-debug-core 6.12.0-55.19.1.el10_0, +6 more
    fixed: vendor fix “To mitigate this issue, prevent module bnxt_en from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.” RHSA-2025:9896
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
13 mo ago

Exploit prediction

0.59% chance of exploitation in the next 30 days, higher than 48% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA ADP 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CNA 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Linux Linux

Classification

Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.