Unfreed socket buffer in Linux kernel team driver broadcast path
Key facts
- Attack vector
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- Privileges required
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- User interaction
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- Attack complexity
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- Impact type
- —
- Confidentiality · integrity · availability
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- Fix status
- Partial Red Hat: 5 without a fix
No CVSS vector from any source. Fix status from CNA and Red Hat.
Summary
The Linux kernel team driver, in versions from 3.6 before 6.18.57 and from 3.6 before 7.2.11 and before 7.3, does not free a socket buffer when a broadcast has no port that can transmit it. The skb is left unconsumed while the transmit path still reports success, so AF_PACKET senders keep their socket write-memory charge. A local user who can send packets through a team device can exhaust socket memory, causing a denial of service.
Written with Claude Haiku 5.5 from the sources below · 2026-11-07
Description from the CNA
In the Linux kernel, the following vulnerability has been resolved: net: team: free skb when broadcast has no txable port bc_transmit() sends the original skb through the last txable port. When no port is txable, it returns false without consuming the skb, but team_xmit() still returns NETDEV_TX_OK. AF_PACKET sends then retain the skb and its socket write-memory charge. A TX-enabled, link-down port keeps the broadcast transmit op installed. Carrier can stay up through a second link-up, TX-disabled port or be forced on by userspace. Free the original skb on the no-port path while leaving the existing drop accounting intact. Discovered by Sashiko during review of previous commit.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
Fixed versions are Linux kernel 6.18.57, 7.2.11 and 7.3. Red Hat Enterprise Linux 7, 8 and 9 and Red Hat OpenShift Container Platform 4 and 5 are affected without a fix, with no fix planned. CISA does not list this vulnerability in its Known Exploited Vulnerabilities catalog.
Written with Claude Haiku 5.5 from the sources below · 2026-11-07
- Fix · CNA Linux (Linux) Fixed in 6.18.57, 7.2.11, 7.3
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet: Fix deferred |
Not affected: 2 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
Timeline
- 2026-10-23 Threatist record created from CVE-2026-99026
- 2026-10-23 Alias added: GHSA-c6m3-gh7v-93hm
- 2026-10-29 Affected versions changed · Red Hat
- 2026-10-29 CVSS score added · Red Hat
- 2026-11-07 Affected versions changed · Red Hat
References
More Linux vulnerabilities
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- TI-2021-02452 Incorrect authorization in Ubuntu linux kernel 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
Sources
- CVE-2026-99026 · CVE Program
- CVE-2026-99026 · NVD
- FIRST EPSS
- GHSA-c6m3-gh7v-93hm · GitHub Advisory Database · CC BY 4.0
- CVE-2026-99026 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences