CVE-2021-47243
Linux Kernel - sch_cape TCP Options Parsing Buffer Overflow
Description
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.
INFO
Published Date :
May 21, 2024, 3:15 p.m.
Last Modified :
Dec. 30, 2024, 7:04 p.m.
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Remotely Exploitable :
No
Impact Score :
5.2
Exploitability Score :
1.8
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-47243.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2021-47243 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-47243 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Dec. 30, 2024
Action Type Old Value New Value Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H Added CWE NIST CWE-125 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.19 up to (excluding) 4.19.196 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.20 up to (excluding) 5.4.128 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.46 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.12.13 *cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:* Changed Reference Type https://git.kernel.org/stable/c/3371392c60e2685af30bd4547badd880f5df2b3f No Types Assigned https://git.kernel.org/stable/c/3371392c60e2685af30bd4547badd880f5df2b3f Patch Changed Reference Type https://git.kernel.org/stable/c/3371392c60e2685af30bd4547badd880f5df2b3f No Types Assigned https://git.kernel.org/stable/c/3371392c60e2685af30bd4547badd880f5df2b3f Patch Changed Reference Type https://git.kernel.org/stable/c/3b491dd593d582ceeb27aa617600712a6bd14246 No Types Assigned https://git.kernel.org/stable/c/3b491dd593d582ceeb27aa617600712a6bd14246 Patch Changed Reference Type https://git.kernel.org/stable/c/3b491dd593d582ceeb27aa617600712a6bd14246 No Types Assigned https://git.kernel.org/stable/c/3b491dd593d582ceeb27aa617600712a6bd14246 Patch Changed Reference Type https://git.kernel.org/stable/c/4cefa061fc63f4d2dff5ab4083f43857cd7a2335 No Types Assigned https://git.kernel.org/stable/c/4cefa061fc63f4d2dff5ab4083f43857cd7a2335 Patch Changed Reference Type https://git.kernel.org/stable/c/4cefa061fc63f4d2dff5ab4083f43857cd7a2335 No Types Assigned https://git.kernel.org/stable/c/4cefa061fc63f4d2dff5ab4083f43857cd7a2335 Patch Changed Reference Type https://git.kernel.org/stable/c/595897ef118d6fe66690c4fc5b572028c9da95b7 No Types Assigned https://git.kernel.org/stable/c/595897ef118d6fe66690c4fc5b572028c9da95b7 Patch Changed Reference Type https://git.kernel.org/stable/c/595897ef118d6fe66690c4fc5b572028c9da95b7 No Types Assigned https://git.kernel.org/stable/c/595897ef118d6fe66690c4fc5b572028c9da95b7 Patch Changed Reference Type https://git.kernel.org/stable/c/ba91c49dedbde758ba0b72f57ac90b06ddf8e548 No Types Assigned https://git.kernel.org/stable/c/ba91c49dedbde758ba0b72f57ac90b06ddf8e548 Patch Changed Reference Type https://git.kernel.org/stable/c/ba91c49dedbde758ba0b72f57ac90b06ddf8e548 No Types Assigned https://git.kernel.org/stable/c/ba91c49dedbde758ba0b72f57ac90b06ddf8e548 Patch -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/3371392c60e2685af30bd4547badd880f5df2b3f Added Reference https://git.kernel.org/stable/c/3b491dd593d582ceeb27aa617600712a6bd14246 Added Reference https://git.kernel.org/stable/c/4cefa061fc63f4d2dff5ab4083f43857cd7a2335 Added Reference https://git.kernel.org/stable/c/595897ef118d6fe66690c4fc5b572028c9da95b7 Added Reference https://git.kernel.org/stable/c/ba91c49dedbde758ba0b72f57ac90b06ddf8e548 -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 28, 2024
Action Type Old Value New Value -
CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 21, 2024
Action Type Old Value New Value Added Description 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. Added Reference kernel.org https://git.kernel.org/stable/c/595897ef118d6fe66690c4fc5b572028c9da95b7 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/4cefa061fc63f4d2dff5ab4083f43857cd7a2335 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/3b491dd593d582ceeb27aa617600712a6bd14246 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/3371392c60e2685af30bd4547badd880f5df2b3f [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/ba91c49dedbde758ba0b72f57ac90b06ddf8e548 [No types assigned]
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-47243 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-47243
weaknesses.