Loading vulnerability…
CVE-2023-4921 is a use-after-free vulnerability in the Linux kernel Traffic Control Quick Fair Queueing (sch_qfq) scheduler. The flaw occurs in qfq_dequeue() when the plug queuing discipline is configured as a class of the qfq queuing discipline and packets are processed. An incorrect sch_plug .peek handler combined with missing error handling in agg_dequeue() causes the invalid memory access.
Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.
What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.
What an attacker gets, and what they’ve been doing with it.
If you can’t patch tonight, do this now.
Patch, then assume compromise.
No public exploits tracked yet. Mallory keeps watching.
No public exploit code observed for this vulnerability.
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.
22 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A high-severity Linux kernel use-after-free flaw in the net/sched sch_qfq queuing discipline. A local attacker with required privileges can trigger the flaw via network packets and escalate privileges.
A use-after-free vulnerability in the Linux kernel sch_qfq network scheduler.
Use-after-free vulnerability in the Linux kernel QFQ network scheduler.
Use-after-free vulnerability in the Linux kernel sch_qfq network scheduler.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.