net: gso: fix ownership in __udp_gso_segment
Priority LOW 34Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 10 fixed, 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: net: gso: fix ownership in __udp_gso_segment In __udp_gso_segment the skb destructor is removed before segmenting the skb but the socket reference is kept as-is. This is an issue if the original skb is later orphaned as we can hit the following bug: kernel BUG at ./include/linux/skbuff.h:3312! (skb_orphan) RIP: 0010:ip_rcv_core+0x8b2/0xca0 Call Trace: ip_rcv+0xab/0x6e0 __netif_receive_skb_one_core+0x168/0x1b0 process_backlog+0x384/0x1100 __napi_poll.constprop.0+0xa1/0x370 net_rx_action+0x925/0xe50 The above can happen following a sequence of events when using OpenVSwitch, when an OVS_ACTION_ATTR_USERSPACE action precedes an OVS_ACTION_ATTR_OUTPUT action: 1. OVS_ACTION_ATTR_USERSPACE is handled (in do_execute_actions): the skb goes through queue_gso_packets and then __udp_gso_segment, where its destructor is removed. 2. The segments' data are copied and sent to userspace. 3. OVS_ACTION_ATTR_OUTPUT is handled (in do_execute_actions) and the same original skb is sent to its path. 4. If it later hits skb_orphan, we hit the bug. Fix this by also removing the reference to the socket in __udp_gso_segment.
Why it matters now
EPSS 0.00243 15th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.4.291, 5.10.235, 5.15.179 +5Red Hat: 2 advisoriesRed Hat: 10 fixed, 2 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 4.18 and later | 5.4.291, 5.10.235, 5.15.179, 6.1.131, 6.6.83, 6.12.19, 6.13.7, 6.14 | Patch available | CNA |
- Linux VendorLinux Affected 4.18 and later Fixed in 5.4.291, 5.10.235, 5.15.179, 6.1.131, 6.6.83, 6.12.19, 6.13.7, 6.14 Patch available CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 4.18 to before 5.4.291; 5.5 to before 5.10.235; 5.11 to before 5.15.179; 5.16 to before 6.1.131; 6.2 to before 6.6.83; 6.7 to before 6.12.19; 6.13 to before 6.13.7 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* | 6.14 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* | 6.14 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* | 6.14 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:* | 6.14 rc4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:* | 6.14 rc5 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.18 to before 5.4.291; 5.5 to before 5.10.235; 5.11 to before 5.15.179; 5.16 to before 6.1.131; 6.2 to before 6.6.83; 6.7 to before 6.12.19; 6.13 to before 6.13.7 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* Versions 6.14 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* Versions 6.14 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* Versions 6.14 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:* Versions 6.14 rc4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:* Versions 6.14 rc5 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.4.291, 5.10.235, 5.15.179, 6.1.131, 6.6.83, 6.12.19, 6.13.7, 6.14
Red Hat 2 advisories
- RHSA-2025:8669 Released 2025-06-09 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-55.16.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.16.1.el10_0, kernel-64k-devel-6.12.0-55.16.1.el10_0 +12
- Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-55.16.1.el10_0, kernel-64k-6.12.0-55.16.1.el10_0, kernel-64k-core-6.12.0-55.16.1.el10_0 +28
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-55.16.1.el10_0, libperf-6.12.0-55.16.1.el10_0
- Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-55.16.1.el10_0, kernel-rt-64k-6.12.0-55.16.1.el10_0, kernel-rt-64k-core-6.12.0-55.16.1.el10_0 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-55.16.1.el10_0, kernel-rt-core-6.12.0-55.16.1.el10_0, kernel-rt-debug-6.12.0-55.16.1.el10_0 +11
- RHSA-2025:8643 Released 2025-06-09 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-570.21.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.21.1.el9_6, kernel-64k-devel-5.14.0-570.21.1.el9_6 +12
- Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-570.21.1.el9_6, kernel-64k-5.14.0-570.21.1.el9_6, kernel-64k-core-5.14.0-570.21.1.el9_6 +28
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-570.21.1.el9_6, libperf-5.14.0-570.21.1.el9_6
- Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-570.21.1.el9_6, kernel-rt-64k-5.14.0-570.21.1.el9_6, kernel-rt-64k-core-5.14.0-570.21.1.el9_6 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-570.21.1.el9_6, kernel-rt-core-5.14.0-570.21.1.el9_6, kernel-rt-debug-5.14.0-570.21.1.el9_6 +11
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2025:8669 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2025:8643 |
| Red Hat Enterprise Linux BaseOS (v. 10) | Fixed | RHSA-2025:8669 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2025:8643 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) | Fixed | RHSA-2025:8669 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) | Fixed | RHSA-2025:8643 |
| Red Hat Enterprise Linux Real Time (v. 10) | Fixed | RHSA-2025:8669 |
| Red Hat Enterprise Linux Real Time (v. 9) | Fixed | RHSA-2025:8643 |
| Red Hat Enterprise Linux Real Time for NFV (v. 10) | Fixed | RHSA-2025:8669 |
| Red Hat Enterprise Linux Real Time for NFV (v. 9) | Fixed | RHSA-2025:8643 |
Not affected: 1 product
- Red Hat Enterprise Linux 6
Timeline
- 2026-10-02 Threatist record created from CVE-2025-21926
- 2026-10-03 Alias added: GHSA-jwp5-c35f-qv38
- 2026-10-29 Affected versions changed · Red Hat
References
Patch 8
- https://git.kernel.org/stable/c/9f28205ddb76e86cac418332e952241d85fed0dc
- https://git.kernel.org/stable/c/a2d1cca955ed34873e524cc2e6e885450d262f05
- https://git.kernel.org/stable/c/455217ac9db0cf9349b3933664355e907bb1a569
- https://git.kernel.org/stable/c/e8db70537878e1bb3fd83e5abcc6feefc0587828
- https://git.kernel.org/stable/c/01a83237644d6822bc7df2c5564fc81b0df84358
- https://git.kernel.org/stable/c/084819b0d8b1bd433b90142371eb9450d657f8ca
- https://git.kernel.org/stable/c/c32da44cc9298eaa6109e3fc2c2b4e07cc4bf11b
- https://git.kernel.org/stable/c/ee01b2f2d7d0010787c2343463965bbc283a497f
More Linux Kernel vulnerabilities
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- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2025-21926 · CVE Program
- CVE-2025-21926 · NVD
- FIRST EPSS
- GHSA-jwp5-c35f-qv38 · GitHub Advisory Database · CC BY 4.0
- CVE-2025-21926 · Red Hat security data · CC BY 4.0
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