All Threat Alerts
criticalCVE Alert
CVE-2026-90235

Critical Vulnerability: CVE-2026-90235

In the Linux kernel, the following vulnerability has been resolved: sunrpc: xprtsock: annotate shared socket callbacks with READ_ONCE/WRITE_ONCE xprtsock replaces and restores sk->sk_data_ready and sk->sk_write_space on live sockets with plain stores, and xs_udp_do_set_buffer_size() invokes sk->sk_write_space via a plain load. These callback pointers are shared with generic socket and protocol paths that may read or invoke them concurrently, so xprtsock needs the same READ_ONCE()/WRITE_ONCE()

Friday, September 18, 2026Vulnios Threat Intelligence
Share:

Vulnerability Snapshot

CVE-2026-90235 is rated CRITICAL โ€” exploitation is trivial or already observed in the wild and impact is severe. Patch immediately, not on the next maintenance window.

Executive Summary

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

sunrpc: xprtsock: annotate shared socket callbacks with READ_ONCE/WRITE_ONCE

xprtsock replaces and restores sk->sk_data_ready and

sk->sk_write_space on live sockets with plain stores, and

xs_udp_do_set_buffer_size() invokes sk->sk_write_space via a plain

load. These callback pointers are shared with generic socket and

protocol paths that may read or invoke them concurrently, so xprtsock

needs the same READ_ONCE()/WRITE_ONCE() callback visibility contract

that the validated 4022 family applied elsewhere.

When SUNRPC takes over an AF_LOCAL, UDP, or TCP socket and later

restores the lower-socket callbacks during teardown, another CPU may

still hold an earlier callback snapshot. The plain replace/restore

pattern leaves the same visibility hole as the validated 4022 family,

so a stale snapshot can still invoke xs_data_ready() or

xs_udp_write_space() after the live callback fields have already been

restored to the lower-s

Why It Matters

CVE-2026-90235 is rated CRITICAL severity, requiring immediate attention from security teams.

CVSS Base Score: 9.8/10

๐Ÿ›ก๏ธWhat Defenders Should Check

  • Check if you are affected โ€” Review your asset inventory for products listed in CVE-2026-90235.
  • Apply available patches โ€” Visit vendor advisories for the latest security updates.
  • Monitor for exploitation โ€” Check your SIEM/IDS logs for related indicators.
  • Use Vulnios to continuously monitor your exposure to CVE-2026-90235 and similar vulnerabilities.

    References & Sources

    How Vulnios Detects This

    Vulnios scans for this vulnerability using Trivy and Grype for SBOM-based CVE matching and Vulnios CVE feed continuous monitoring against your asset inventory. Run a scan against your environment to see whether you are exposed; findings are linked back to the original CVE record so triage starts with the patch path already known.

    AI Security Advisor

    Powered by Gemini

    Get AI-powered security recommendations tailored to this specific threat โ€” including risk assessment, detection guidance, MITRE ATT&CK mapping, and actionable remediation steps.

    Sources

    Related Threat Alerts

    Frequently Asked Questions

    What is CVE-2026-90235?

    CVE-2026-90235 is a critical-severity vulnerability tracked under the Common Vulnerabilities and Exposures program. In the Linux kernel, the following vulnerability has been resolved:

    sunrpc: xprtsock: annotate shared socket callbacks with READ_ONCE/WRITE_ONCE

    xprtsock replaces and restores sk->sk_data_ready and

    Am I affected?

    Affected technology is listed in the Affected Products section above. If your asset inventory contains any of them, assume in-scope until you can prove otherwise.

    How urgent is the response?

    Critical: do not wait for your normal patch cycle. Verify exposure today, apply the vendor patch immediately, and add detection rules for any post-exploit indicators.

    How do I remediate?

    Apply the vendor patch listed in the upstream advisory linked under Sources. If the patch is not yet available, follow the vendor-supplied workaround (often a config flag or feature disable) and add detections for the published exploit pattern in your SIEM. Re-scan after the patch lands to confirm the finding clears.

    Where can I track exploitation activity?

    Watch CISA's Known Exploited Vulnerabilities catalog for CVE-2026-90235. Cross-reference with public exploit databases and your own SIEM/IDS for indicator-of-compromise patterns. Vulnios tracks KEV status automatically and surfaces it on the asset findings view.

    How does Vulnios help with this?

    Vulnios continuously cross-references your asset inventory against the live CVE feed (NVD, vendor advisories, CISA KEV, and curated OSINT). When a new CVE matches your environment, you get a prioritized finding with the severity, KEV status, exploit-prediction (EPSS), and a direct path to the vendor patch. You can start a free scan from the homepage.

    critical

    Protect Your Organization

    Monitor CVEs, scan for vulnerabilities, and get real-time threat alerts โ€” all in one platform.

    Weekly threat digest

    KEV-listed exploits and vendor advisories, every Monday.

    One email a week. Unsubscribe any time.

    Get instant alerts on Telegram

    Join our public channel for real-time critical CVE alerts.

    Follow @vulnios