bpf: don't rewrite bpf_fastcall patterns entered by a jump (CVE-2026-98048) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-98048

bpf: don't rewrite bpf_fastcall patterns entered by a jump

Answer in brief

CVE-2026-98048 records a Unknown severity vulnerability in bpf: don't rewrite bpf_fastcall patterns entered by a jump. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 25, 2026Updated Sep 25, 2026Source checked Sep 25, 2026First seen by HOL Sep 25, 2026Material review Sep 25, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=5b5f51bff1b66cedb62b5ba74a1878341204e057 <24adbc2c3bbe3385ce922587e1f8e837a68b3e25 \|\| >=5b5f51bff1b66cedb62b5ba74a1878341204e057 <0b1c83dc3c4401cd7e846548f62e3caf3d06742e	24adbc2c3bbe3385ce922587e1f8e837a68b3e25, 0b1c83dc3c4401cd7e846548f62e3caf3d06742e
Linux/Linuxgeneric	6.12	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 24adbc2c3bbe3385ce922587e1f8e837a68b3e25 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 25, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: bpf: don't rewrite bpf_fastcall patterns entered by a jump mark_fastcall_pattern_for_call() must ensure that matched "spill; call; fill" instruction series is not interrupted by a jump. Otherwise the rewrite applied by bpf_remove_fastcall_spills_fills() is not sound. Record the instructions targeted by jumps in insn_aux_data[*].jump_target when the CFG is built and use this flag to stop growing a pattern at such an instruction. Jumps to the first spill are fine. Note that existing insn_aux_data[*].jmp_point field can't be reused, as it marks subprogram return instructions.

Quoted source text, attributed separately from HOL analysis.