Bug 2536197 (CVE-2026-93043)

Summary:	CVE-2026-93043 kernel: bpf: Disallow interpreter fallback for gotox insn
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the Linux kernel's Berkeley Packet Filter (BPF) component. A local attacker could craft a BPF program that uses an `insn_array` map with a specific instruction (`BPF_JMP\|BPF_JA\|BPF_X`) not recognized by the BPF interpreter. This misinterpretation leads to a kernel bug, causing a system crash and resulting in a Denial of Service (DoS).	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-09-17 16:45:34 UTC

In the Linux kernel, the following vulnerability has been resolved:

bpf: Disallow interpreter fallback for gotox insn

The interpreter does not recognize the BPF_JMP|BPF_JA|BPF_X insn, which
is used for insn_array map. Thereafter, it would hit the BUG_ON() in
___bpf_prog_run() at run time.

[    2.563726] BPF interpreter: unknown opcode 0d (imm: 0x0)
[    2.564557] ------------[ cut here ]------------
[    2.565206] kernel BUG at kernel/bpf/core.c:2349!
[    2.565882] Oops: invalid opcode: 0000 [#1] SMP PTI

Set jit_required as true when insn_array map is used in the prog in
order to disallow interpreter fallback for gotox insn in
core.c::__bpf_prog_select_runtime().

Comment 1 gkamathe 2026-09-19 19:20:36 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-93043.mbox