In the Linux kernel, the following vulnerability has been resolved: bpf: Propagate error from visit_tailcall_insn Commit e40f5a6bf88a ("bpf: correct… (CVE-2026-63864)
A vulnerability in the Linux kernel related to the eBPF subsystem was resolved by ensuring that the return value of the visit_tailcall_insn() function is properly checked. The issue involved the lack of error propagation from this function, which was introduced in commit e40f5a6bf88a. This fix corrects stack liveness handling for tail calls in eBPF programs.
AI Analysis
Technical Summary
The vulnerability CVE-2026-63864 in the Linux kernel concerns the eBPF component where the function visit_tailcall_insn() was added without checking its return value. This omission could lead to improper error handling during tail call instructions in eBPF programs. The issue was addressed by updating the kernel to propagate errors correctly from visit_tailcall_insn(), improving the correctness of stack liveness tracking for tail calls.
Potential Impact
The vulnerability affects the Linux kernel's eBPF subsystem by potentially allowing improper error handling in tail call instructions. The specific impact details, such as privilege escalation or denial of service, are not provided in the available data. No known exploits in the wild have been reported.
Mitigation Recommendations
A fix has been applied in the Linux kernel source code by commit e40f5a6bf88a which corrects the error propagation from visit_tailcall_insn(). Users should update their Linux kernel to a version that includes this commit or later to remediate the vulnerability. Patch status is confirmed by the presence of this commit; no additional vendor advisory was provided.
In the Linux kernel, the following vulnerability has been resolved: bpf: Propagate error from visit_tailcall_insn Commit e40f5a6bf88a ("bpf: correct… (CVE-2026-63864)
Description
A vulnerability in the Linux kernel related to the eBPF subsystem was resolved by ensuring that the return value of the visit_tailcall_insn() function is properly checked. The issue involved the lack of error propagation from this function, which was introduced in commit e40f5a6bf88a. This fix corrects stack liveness handling for tail calls in eBPF programs.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-63864 in the Linux kernel concerns the eBPF component where the function visit_tailcall_insn() was added without checking its return value. This omission could lead to improper error handling during tail call instructions in eBPF programs. The issue was addressed by updating the kernel to propagate errors correctly from visit_tailcall_insn(), improving the correctness of stack liveness tracking for tail calls.
Potential Impact
The vulnerability affects the Linux kernel's eBPF subsystem by potentially allowing improper error handling in tail call instructions. The specific impact details, such as privilege escalation or denial of service, are not provided in the available data. No known exploits in the wild have been reported.
Mitigation Recommendations
A fix has been applied in the Linux kernel source code by commit e40f5a6bf88a which corrects the error propagation from visit_tailcall_insn(). Users should update their Linux kernel to a version that includes this commit or later to remediate the vulnerability. Patch status is confirmed by the presence of this commit; no additional vendor advisory was provided.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-xw7r-6m22-6cfw
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-63864"]
- Ecosystems
- []
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a5d27ac2a4a8d598913063a
Added to database: 07/19/2026, 19:38:20 UTC
Last enriched: 07/19/2026, 20:14:39 UTC
Last updated: 07/20/2026, 17:26:47 UTC
Views: 9
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