Answer in brief
CVE-2026-31526 records a Unknown severity vulnerability in bpf: Fix exception exit lock checking for subprogs. 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.
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.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | 6.7 | Not reported |
| Linux/Linuxgeneric | >=f18b03fabaa9b7c80e80b72a621f481f0d706ae0 <4eca06a55417c3b2e538656d12c89e224343653e || >=f18b03fabaa9b7c80e80b72a621f481f0d706ae0 <c0281da1f2aa5c2fca3a05f79b86bea96591c358 || >=f18b03fabaa9b7c80e80b72a621f481f0d706ae0 <5a399f3117642494e35545f6ca397d3e177c1f9b || >=f18b03fabaa9b7c80e80b72a621f481f0d706ae0 <6c2128505f61b504c79a20b89596feba61388112 | 4eca06a55417c3b2e538656d12c89e224343653e, c0281da1f2aa5c2fca3a05f79b86bea96591c358, 5a399f3117642494e35545f6ca397d3e177c1f9b, 6c2128505f61b504c79a20b89596feba61388112 |
Published upstream
Apr 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 21, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 21, 2026
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix exception exit lock checking for subprogs process_bpf_exit_full() passes check_lock = !curframe to check_resource_leak(), which is false in cases when bpf_throw() is called from a static subprog. This makes check_resource_leak() to skip validation of active_rcu_locks, active_preempt_locks, and active_irq_id on exception exits from subprogs. At runtime bpf_throw() unwinds the stack via ORC without releasing any user-acquired locks, which may cause various issues as the result. Fix by setting check_lock = true for exception exits regardless of curframe, since exceptions bypass all intermediate frame cleanup. Update the error message prefix to "bpf_throw" for exception exits to distinguish them from normal BPF_EXIT. Fix reject_subprog_with_rcu_read_lock test which was previously passing for the wrong reason. Test program returned directly from the subprog call without closing the RCU section, so the error was triggered by the unclosed RCU lock on normal exit, not by bpf_throw. Update __msg annotations for affected tests to match the new "bpf_throw" error prefix. The spin_lock case is not affected because they are already checked [1] at the call site in do_check_insn() before bpf_throw can run. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/kernel/bpf/verifier.c?h=v7.0-rc4#n21098
Quoted source text, attributed separately from HOL analysis.