CVE-2026-97942 json
x86/alternatives: Exclude text poking against change_page_attr()
published last mo. modified 24d ago also EUVD-2026-86796
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 10%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
x86/alternatives: Exclude text poking against change_page_attr()
From time to time, the following BUG can be observed in the x86 alternatives patching code [0]:
> kernel BUG at arch/x86/kernel/alternative.c:2576! > Oops: invalid opcode: 0000 [#1] SMP NOPTI > CPU: 0 UID: 0 PID: 355 Comm: (udev-worker) Not tainted 7.1.3-1-default #1 PREEMPT(full) openSUSE Tumbleweed 8c1795b03ec64f997e57a8ad38b1161e3b98da64 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS unknown 02/02/2022 > RIP: 0010:__text_poke+0x2aa/0x450 > Call Trace: > <TASK> > smp_text_poke_batch_finish+0x2a7/0x320 > __static_call_transform+0xb7/0x220 > arch_static_call_transform+0x5b/0xb0 > __static_call_init+0xe9/0x270 > static_call_module_notify+0x11f/0x150 > notifier_call_chain+0x61/0xe0 > blocking_notifier_call_chain_robust+0x63/0xc0 > load_module+0x1c92/0x20c0 > init_module_from_file+0xd8/0x140 > idempotent_init_module+0x100/0x2f0 > __x64_sys_finit_module+0x71/0xe0 > do_syscall_64+0xe1/0x610 > entry_SYSCALL_64_after_hwframe+0x76/0x7e
which matches the following BUG_ON() in alternative.c:
/* * If something went wrong, crash and burn since recovery paths are not * implemented. */ BUG_ON(!pages[0] || (cross_page_boundary && !pages[1]));
This can happen if vmalloc_to_page() fails, for any reason. Such can happen if text poking races with CPA, which can possibly result in the collapsing of page tables (or breaking of PMD hugepages). It is not a problem for most users of vmalloc_to_page() (they solely own the vmalloc'd range) but, when CONFIG_ARCH_HAS_EXECMEM_ROX=y, various modules own a single execmem vmalloc range, and can call set_memory_*() in parallel on it. This can happen to race against __text_poke and cause havoc in vmalloc_to_page().
Fix it by excluding against CPA using the init_mm mmap read lock.
[ dhansen: Fix up SoB ordering. The actual code flow here was: Pedro=>Lorenzo=>Mike=>Me which is reflected in the SoB chain now. I *believe* Mike simply picked up Lorenzo's update to Pedro's post from the Link ]
Patch / fix
- Linux Linux 6.18.53, 7.2.7, 7.3
- linux Debian 14 7.2.7-1
debian advisories DEBIAN-CVE-2026-97942
- linux Ubuntu 26.04 LTS 7.0.0-42.42
- linux-aws Ubuntu 26.04 LTS 7.0.0-1016.17
- linux-gcp Ubuntu 26.04 LTS 7.0.0-1016.18
- linux-ibm Ubuntu 26.04 LTS 7.0.0-1017.17
- linux-riscv Ubuntu 26.04 LTS 7.0.0-42.42.1
- linux-oracle Ubuntu 26.04 LTS 7.0.0-1015.16
- linux-hwe-7.0 Ubuntu 24.04 LTS 7.0.0-42.42~24.04.1
- linux-oem-7.0 Ubuntu 26.04 LTS 7.0.0-1017.17
ubuntu advisories UBUNTU-CVE-2026-97942
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel-rt Linux Micro 6.2 6.12.0-160000.40.1
- kernel-64kb SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.40.1
- kernel-source SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.40.1
- kernel-default SLES 16.0, SLE High Availability Extension 16.0, Linux Micro 6.2 +1 more 6.12.0-160000.40.1
- kernel-default-base SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.40.1.160000.2.29
- kernel-syms SLES 16.0, Linux Micro Extras 6.2, SLES for SAP applications 16.0 6.12.0-160000.40.1
- kernel-azure SLES for SAP applications 16.0, SLES 16.0 6.12.0-160000.40.1
- kernel-obs-qa SLES for SAP applications 16.0, SLES 16.0 6.12.0-160000.40.1
suse advisories SUSE-SU-2026:24422-1SUSE-SU-2026:24446-1SUSE-SU-2026:24437-1SUSE-SU-2026:24386-1
- kernel-rt openSUSE Leap 16.0 6.12.0-160000.40.1
- dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.40.1
- kernel-64kb openSUSE Leap 16.0 6.12.0-160000.40.1
- kernel-syms openSUSE Leap 16.0 6.12.0-160000.40.1
- kernel-azure openSUSE Leap 16.0 6.12.0-160000.40.1
- kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.40.1
- kernel-source openSUSE Leap 16.0 6.12.0-160000.40.1
- kernel-default openSUSE Leap 16.0 6.12.0-160000.40.1
opensuse advisories openSUSE-SU-2026:22167-1openSUSE-SU-2026:12074-1
Is CVE-2026-97942 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerVendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-97942 updated cvss 5.5
kernel: x86/alternatives: Exclude text poking against change_page_attr()
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Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 moreaffected: workaround, no fix planned “Out of support scope”
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Red Hat Enterprise Linux 10 kernelaffected: workaround, no fix available “Fix deferred”
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Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9not affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.20% chance of exploitation in the next 30 days, higher than 10% of all scored CVEs (FIRST EPSS, 2026-11-11).
Affected products
- Linux Linux
Classification
- Technology feeds
References
Sources
- CVE List CVE-2026-97942
- NVD CVE-2026-97942
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.