cbcvebase.
CVE-2021-47243
published 2024-05-21

CVE-2021-47243: In the Linux kernel, the following vulnerability has been resolved: sch_cake: Fix out of bounds when parsing TCP options and header The TCP option parser in…

PriorityP430high7.1CVSS 3.1
AVLACLPRLUINSUCHINAH
EPSS
0.26%
17.6th percentile
In the Linux kernel, the following vulnerability has been resolved: sch_cake: Fix out of bounds when parsing TCP options and header The TCP option parser in cake qdisc (cake_get_tcpopt and cake_tcph_may_drop) could read one byte out of bounds. When the length is 1, the execution flow gets into the loop, reads one byte of the opcode, and if the opcode is neither TCPOPT_EOL nor TCPOPT_NOP, it reads one more byte, which exceeds the length of 1. This fix is inspired by commit 9609dad263f8 ("ipv4: tcp_input: fix stack out of bounds when parsing TCP options."). v2 changes: Added doff validation in cake_get_tcphdr to avoid parsing garbage as TCP header. Although it wasn't strictly an out-of-bounds access (memory was allocated), garbage values could be read where CAKE expected the TCP header if doff was smaller than 5.

Affected

16 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.46-1 (bookworm)linux 5.10.46-1 (bookworm)
linuxlinux
linuxlinux>= 8b7138814f29933898ecd31dfc83e35a30ee69f5 < 595897ef118d6fe66690c4fc5b572028c9da95b7595897ef118d6fe66690c4fc5b572028c9da95b7
linuxlinux>= 8b7138814f29933898ecd31dfc83e35a30ee69f5 < 4cefa061fc63f4d2dff5ab4083f43857cd7a23354cefa061fc63f4d2dff5ab4083f43857cd7a2335
linuxlinux>= 8b7138814f29933898ecd31dfc83e35a30ee69f5 < 3b491dd593d582ceeb27aa617600712a6bd142463b491dd593d582ceeb27aa617600712a6bd14246
linuxlinux>= 8b7138814f29933898ecd31dfc83e35a30ee69f5 < 3371392c60e2685af30bd4547badd880f5df2b3f3371392c60e2685af30bd4547badd880f5df2b3f
linuxlinux>= 8b7138814f29933898ecd31dfc83e35a30ee69f5 < ba91c49dedbde758ba0b72f57ac90b06ddf8e548ba91c49dedbde758ba0b72f57ac90b06ddf8e548
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 4.19 < 4.19.1964.19.196
linuxlinux_kernel>= 4.20 < 5.4.1285.4.128
linuxlinux_kernel>= 5.11 < 5.12.135.12.13
linuxlinux_kernel>= 5.5 < 5.10.465.10.46

CVSS provenance

nvdv3.17.1HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
osv7.1HIGH
vendor_debian7.1HIGH
vendor_redhat7.1HIGH
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