cbcvebase.
CVE-2025-21700
published 2025-02-13

CVE-2025-21700: In the Linux kernel, the following vulnerability has been resolved: net: sched: Disallow replacing of child qdisc from one parent to another Lion Ackermann was…

PriorityP340high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.23%
13.7th percentile
In the Linux kernel, the following vulnerability has been resolved: net: sched: Disallow replacing of child qdisc from one parent to another Lion Ackermann was able to create a UAF which can be abused for privilege escalation with the following script Step 1. create root qdisc tc qdisc add dev lo root handle 1:0 drr step2. a class for packet aggregation do demonstrate uaf tc class add dev lo classid 1:1 drr step3. a class for nesting tc class add dev lo classid 1:2 drr step4. a class to graft qdisc to tc class add dev lo classid 1:3 drr step5. tc qdisc add dev lo parent 1:1 handle 2:0 plug limit 1024 step6. tc qdisc add dev lo parent 1:2 handle 3:0 drr step7. tc class add dev lo classid 3:1 drr step 8. tc qdisc add dev lo parent 3:1 handle 4:0 pfifo step 9. Display the class/qdisc layout tc class ls dev lo class drr 1:1 root leaf 2: quantum 64Kb class drr 1:2 root leaf 3: quantum 64Kb class drr 3:1 root leaf 4: quantum 64Kb tc qdisc ls qdisc drr 1: dev lo root refcnt 2 qdisc plug 2: dev lo parent 1:1 qdisc pfifo 4: dev lo parent 3:1 limit 1000p qdisc drr 3: dev lo parent 1:2 step10. trigger the bug

Affected

30 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.129-1 (bookworm)linux 6.1.129-1 (bookworm)
debianlinux-6.1< linux 6.1.129-1 (bookworm)linux 6.1.129-1 (bookworm)
googlechrome_chrome
linuxlinux
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < cd796e269123e1994bfc4e99dd76680ba0946a97cd796e269123e1994bfc4e99dd76680ba0946a97
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < fe18c21d67dc7d1bcce1bba56515b1b0306db19bfe18c21d67dc7d1bcce1bba56515b1b0306db19b
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 38646749d6e12f9d80a08d21ca39f0beca20230d38646749d6e12f9d80a08d21ca39f0beca20230d
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < deda09c0543a66fa51554abc5ffd723d99b191bfdeda09c0543a66fa51554abc5ffd723d99b191bf
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 7e2bd8c13b07e29a247c023c7444df23f9a79fd87e2bd8c13b07e29a247c023c7444df23f9a79fd8
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 73c7e1d6898ccbeee126194dcc05f58b8a795e7073c7e1d6898ccbeee126194dcc05f58b8a795e70
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 46c59ec33ec98aba20c15117630cae43a01404cc46c59ec33ec98aba20c15117630cae43a01404cc
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < bc50835e83f60f56e9bec2b392fb5544f250fb6fbc50835e83f60f56e9bec2b392fb5544f250fb6f
linuxlinux_kernel>= 0 < 5.10.237-15.10.237-1
linuxlinux_kernel>= 0 < 6.1.129-16.1.129-1
linuxlinux_kernel>= 0 < 6.12.13-16.12.13-1
linuxlinux_kernel>= 0 < 6.12.13-16.12.13-1
linuxlinux_kernel>= 0 < 5.4.0-214.2345.4.0-214.234
linuxlinux_kernel>= 0 < 5.15.0-138.1485.15.0-138.148
linuxlinux_kernel>= 0 < 6.8.0-58.606.8.0-58.60
linuxlinux_kernel>= 0 < 4.4.0-267.3014.4.0-267.301
linuxlinux_kernel>= 0 < 4.15.0-236.2484.15.0-236.248
linuxlinux_kernel>= 2.6.12 < 5.4.2915.4.291
linuxlinux_kernel>= 5.11 < 5.15.1795.15.179
linuxlinux_kernel>= 5.16 < 6.1.1296.1.129
linuxlinux_kernel>= 5.5 < 5.10.2355.10.235

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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