CVE-2021-47243
sch_cake: Fix out of bounds when parsing TCP options and header
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
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.
En el kernel de Linux, se resolvió la siguiente vulnerabilidad: sch_cake: Corrección de límites al analizar las opciones TCP y el encabezado. El analizador de opciones TCP en cake qdisc (cake_get_tcpopt y cake_tcph_may_drop) podía leer un byte fuera de los límites. Cuando la longitud es 1, el flujo de ejecución entra en el bucle, lee un byte del código de operación y, si el código de operación no es TCPOPT_EOL ni TCPOPT_NOP, lee un byte más, que excede la longitud de 1. Esta solución está inspirada en la confirmación. 9609dad263f8 ("ipv4: tcp_input: corrige la pila fuera de los límites al analizar las opciones de TCP"). Cambios en v2: Se agregó validación de doff en cake_get_tcphdr para evitar analizar basura como encabezado TCP. Aunque no era estrictamente un acceso fuera de los límites (se asignó memoria), se podían leer valores basura donde CAKE esperaba el encabezado TCP si doff era menor que 5.
CVSS Scores
SSVC
- Decision:Track
Timeline
- 2024-04-10 CVE Reserved
- 2024-05-21 CVE Published
- 2024-05-22 EPSS Updated
- 2024-12-19 CVE Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
CAPEC
References (6)
| URL | Tag | Source |
|---|---|---|
| https://git.kernel.org/stable/c/8b7138814f29933898ecd31dfc83e35a30ee69f5 | Vuln. Introduced |
| URL | Date | SRC |
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| URL | Date | SRC |
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Affected Vendors, Products, and Versions
| Vendor | Product | Version | Other | Status | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.19 < 4.19.196 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.19 < 4.19.196" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.19 < 5.4.128 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.19 < 5.4.128" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.19 < 5.10.46 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.19 < 5.10.46" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.19 < 5.12.13 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.19 < 5.12.13" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 4.19 < 5.13 Search vendor "Linux" for product "Linux Kernel" and version " >= 4.19 < 5.13" | en |
Affected
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