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CVE-2023-3609 is a double-free vulnerability in the Linux kernel Network Scheduler cls_u32 traffic-control classifier. In u32_set_parms(), failure of tcf_change_indev() can cause an early error return after tcf_bind_filter() has modified a reference count. An attacker able to manipulate the reference count to zero can cause the referenced object to be freed while it remains reachable, resulting in use-after-free/double-free memory corruption.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
This repository contains a full local privilege escalation exploit for Linux kernel CVE-2023-3609 (net/sched/cls_u32 use-after-free). The exploit targets kernels from v4.14-rc1 to v6.5-rc7 and requires CAP_NET_ADMIN, user namespaces, and specific kernel configs. The structure includes two main exploit directories for different kernel environments (cos-97-16919.294.28 and mitigation-6.1), each with a Makefile, C source for the exploit logic (poc.c), post-exploitation root shell (root.c), assembly and Python scripts for shellcode generation, and a shell script for packaging and running the exploit. The exploit works by manipulating qdisc class reference counters, spraying kernel heap objects, and leveraging eBPF JIT spraying to gain RIP control. It overwrites /proc/sys/kernel/core_pattern to execute a file descriptor containing a root shell binary upon coredump, effectively granting root shell access in the initial namespace. The exploit is operational and includes all necessary payloads and setup scripts for reliable exploitation.
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33 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Linux kernel net/sched cls_u32 reference-counter leak.
Linux kernel net/sched cls_u32 reference-counter leak.
Linux kernel net/sched cls_u32 reference-count leak when tcf_change_indev() fails.
Linux kernel traffic-control cls_u32 reference-counter leak.
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.