CVE-2026-46031: net: ks8851: Reinstate disabling of BHs around IRQ handler
Noroxi assessment
Priority: Monitor (action score 30/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.37% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: Linux Linux 1962027a6d223f90df8b372929f9d1a8d321ad6a, 21f1707a8e978558dcb11b053855521e32ac0eec, 518040324067d8efaa2da1992297b7e7bf5640f4; azl3 kernel 6.6.139.1-1 on Azure Linux 3.0 6.6.141.1-1.
Low priority for now. Upgrade to Linux Linux 1962027a6d223f90df8b372929f9d1a8d321ad6a, 21f1707a8e978558dcb11b053855521e32ac0eec, 518040324067d8efaa2da1992297b7e7bf5640f4; azl3 kernel 6.6.139.1-1 on Azure Linux 3.0 6.6.141.1-1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In the Linux kernel, the following vulnerability has been resolved: net: ks8851: Reinstate disabling of BHs around IRQ handler If the driver executes ks8851_irq() AND a TX packet has been sent, then the driver enables TX queue via netif_wake_queue() which schedules TX softirq to queue packets for this device. If CONFIG_PREEMPT_RT=y is set AND a packet has also been received by the MAC, then ks8851_rx_pkts() calls netdev_alloc_skb_ip_align() to allocate SKBs for the received packets. If netdev_alloc_skb_ip_align() is called with BH enabled, then local_bh_enable() at the end of netdev_alloc_skb_ip_align() will trigger the pending softirq processing, which may ultimately call the .xmit callback ks8851_start_xmit_par(). The ks8851_start_xmit_par() will try to lock struct ks8851_net_par .lock spinlock, which is already locked by ks8851_irq() from which ks8851_start_xmit_par() was called. This leads to a deadlock, which is reported by the kernel, including a trace listed below. If CONFIG_PREEMPT_RT is not set, then since commit 0913ec336a6c0 ("net: ks8851: Fix deadlock with the SPI chip variant") the deadlock can also be triggered without received packet in the RX FIFO. The pending softirqs will be processed on return from spin_unlock_bh(&ks->statelock) in ks8851_irq(), which triggers the deadlock as well. Fix the problem by disabling BH around critical sections, including the IRQ handler, thus preventing the net_tx_action() softirq from triggering during these critical sections. The net_tx_action() softirq is triggered once BH are re-enabled and at the end of the IRQ handler, once all the other IRQ handler actions have been completed. __schedule from schedule_rtlock+0x1c/0x34 schedule_rtlock from rtlock_slowlock_locked+0x548/0x904 rtlock_slowlock_locked from rt_spin_lock+0x60/0x9c rt_spin_lock from ks8851_start_xmit_par+0x74/0x1a8 ks8851_start_xmit_par from netdev_start_xmit+0x20/0x44 netdev_start_xmit from dev_hard_start_xmit+0xd0/0x188 dev_hard_start_xmit from sch_direct_xmit+0xb8/0x25c sch_direct_xmit from __qdisc_run+0x1f8/0x4ec __qdisc_run from qdisc_run+0x1c/0x28 qdisc_run from net_tx_action+0x1f0/0x268 net_tx_action from handle_softirqs+0x1a4/0x270 handle_softirqs from __local_bh_enable_ip+0xcc/0xe0 __local_bh_enable_ip from __alloc_skb+0xd8/0x128 __alloc_skb from __netdev_alloc_skb+0x3c/0x19c __netdev_alloc_skb from ks8851_irq+0x388/0x4d4 ks8851_irq from irq_thread_fn+0x24/0x64 irq_thread_fn from irq_thread+0x178/0x28c irq_thread from kthread+0x12c/0x138 kthread from ret_from_fork+0x14/0x28
- Published
- May 27, 2026
- Updated
- Aug 5, 2026
- EPSS
- 0.3% · 31th percentile
- CWE
- CWE-667
Report tools
Action score
30
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.3%
CNA vs NVD score
- NVD
- —
- CNA · Linux
- 7.5
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Running WordPress? Scan your site free with WP Lens
Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel6.1.91 and later · before 6.1.175
- linux linux kernel6.6.31 and later · before 6.6.140
- linux linux kernel6.8.10 and later · before 6.9
- linux linux kernel6.9.1 and later · before 6.12.86
- linux linux kernel6.13 and later · before 6.18.27
- linux linux kernel6.19 and later · before 7.0.4
- linux linux kernel6.9
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 7e2901a2a9195da76111f351584bf77552a038f0, 6.9affected
- 8a3ff43dcbab7c96f9e8cf2bd1049ab8d6e59545 and later · before 1962027a6d223f90df8b372929f9d1a8d321ad6aaffected · git
- ae87f661f3c1a3134a7ed86ab69bf9f12af88993 and later · before 640a7631d31db87d5fa1b34cea44a99b6e78854baffected · git
- e0863634bf9f7cf36291ebb5bfa2d16632f79c49 and later · before 518040324067d8efaa2da1992297b7e7bf5640f4affected · git
- e0863634bf9f7cf36291ebb5bfa2d16632f79c49 and later · before be8aad558b4675f45b43080f81a9ffdeddea73a5affected · git
- e0863634bf9f7cf36291ebb5bfa2d16632f79c49 and later · before 21f1707a8e978558dcb11b053855521e32ac0eecaffected · git
- e0863634bf9f7cf36291ebb5bfa2d16632f79c49 and later · before 5c9fcac3c872224316714d0d8914d9af16c76a6daffected · git
- 6.1.91 and later · before 6.1.175affected · semver
- 6.6.31 and later · before 6.6.140affected · semver
- 6.8.10 and later · before 6.9affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | before 6.1.176-1 | 6.1.176-1 |
| Debian:13 | linux | before 6.12.86-1 | 6.12.86-1 |
| Debian:14 | linux | before 7.0.4-1 | 7.0.4-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV90Now
- CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
Published before and after this one in the same product
- ← EarlierCVE-2026-46029May 27, 2026 · mm/slab: return NULL early from kmalloc_nolock() in NMI on UP28Monitor
- ← EarlierCVE-2026-46030May 27, 2026 · EDAC/versalnet: Fix device_node leak in mc_probe()22Monitor
- Later →CVE-2026-46034May 27, 2026 · vfio/cdx: Fix NULL pointer dereference in interrupt trigger path22Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 1962027a6d223f90df8b372929f9d1a8d321ad6a | Vendor (CNA) |
| Linux Linux | 21f1707a8e978558dcb11b053855521e32ac0eec | Vendor (CNA) |
| Linux Linux | 518040324067d8efaa2da1992297b7e7bf5640f4 | Vendor (CNA) |
| Linux Linux | 5c9fcac3c872224316714d0d8914d9af16c76a6d | Vendor (CNA) |
| Linux Linux | 6.1.175 | Vendor (CNA) |
| Linux Linux | 6.6.140 | Vendor (CNA) |
| Linux Linux | 6.9 | Vendor (CNA) |
| Linux Linux | 640a7631d31db87d5fa1b34cea44a99b6e78854b | Vendor (CNA) |
| Linux Linux | be8aad558b4675f45b43080f81a9ffdeddea73a5 | Vendor (CNA) |
| azl3 kernel 6.6.139.1-1 on Azure Linux 3.0 | 6.6.141.1-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| debian:linux | 6.1.176-1 · Debian:12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-667 · Improper LockingCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (5 more)Show less
- git.kernel.org/stable/c/21f1707a8e978558dcb11b053855521e32ac0eec
- git.kernel.org/stable/c/518040324067d8efaa2da1992297b7e7bf5640f4
- git.kernel.org/stable/c/5c9fcac3c872224316714d0d8914d9af16c76a6d
- git.kernel.org/stable/c/640a7631d31db87d5fa1b34cea44a99b6e78854b
- git.kernel.org/stable/c/be8aad558b4675f45b43080f81a9ffdeddea73a5
Vendor advisories and official records. Exploit/PoC links are deliberately left out.