Linux kernel BPF accepts packet pointers in mutating subprograms
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
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- Confidentiality · integrity · availability
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- Fix status
- Partial Red Hat: 6 without a fix
No CVSS vector from any source. Fix status from CNA and Red Hat.
Summary
The Linux kernel BPF verifier accepts PTR_TO_PACKET pointers passed to subprograms that may mutate packet memory, so the pointer can become invalid when a pskb_* call changes the packet. The affected range is from 0 before 7.2.9 in the Linux kernel. The flaw is in the verifier's handling of packet pointer bounds across subprogram boundaries.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Description from the CNA
In the Linux kernel, the following vulnerability has been resolved: bpf: Reject pkt arguments in mutating subprogs The verifier tracks changes in how PTR_TO_PACKET registers' bounds are modified across subprog boundaries. PTR_TO_PACKET registers are actually passed as PTR_TO_MEM, which is assumed valid for the entire call. This is not the case with packet memory, where a pskb_* call may invalidate its memory region. Reject BPF code that passes PTR_TO_PACKET pointers to subprogs that may mutate a packet. We cannot pass the pointer as a true PTR_TO_PACKET because we would also need to somehow pass the PTR_TO_PACKET_META or PTR_TO_PACKET_END to the subprog. Since we cannot avoid representing the pointer in the subprog as PTR_TO_MEM, only permit it if the subprog is guaranteed not to mutate the packet.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
Upgrade the Linux kernel to 7.2.9 or 7.3, which contain the fix. Red Hat Enterprise Linux 7, 8, 9 and 10 and Red Hat OpenShift Container Platform 4 and 5 are listed as affected with no fix available.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
- Fix · CNA Linux (Linux) Fixed in 7.2.9
- Fix · CNA Linux (Linux) Fixed in 7.2.9, 7.3
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| 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: 1 product
- Red Hat Enterprise Linux 6
Timeline
- 2026-10-18 Threatist record created from CVE-2026-98589
- 2026-10-18 Alias added: GHSA-2cxv-r576-wfcv
- 2026-10-19 Fix available: Linux/[email protected] · CNA
- 2026-10-20 Affected versions changed · Red Hat
- 2026-10-20 CVSS score added · Red Hat
- 2026-10-30 Affected versions changed · Red Hat
References
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Sources
- CVE-2026-98589 · CVE Program
- CVE-2026-98589 · NVD
- FIRST EPSS
- GHSA-2cxv-r576-wfcv · GitHub Advisory Database · CC BY 4.0
- CVE-2026-98589 · 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