CVE-2021-47245
Last modified
CVE-2021-47245 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: netfilter: synproxy: Fix out of bounds when parsing TCP options The TCP option parser in synproxy (synproxy_parse_options) 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 an early return when length < 0 to avoid calling skb_header_pointer with negative length.. EPSS estimates a 0.26% chance of exploitation in the next 30 days.
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: synproxy: Fix out of bounds when parsing TCP options The TCP option parser in synproxy (synproxy_parse_options) 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 an early return when length < 0 to avoid calling skb_header_pointer with negative length.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Linux | Linux Kernel | >= 3.12, < 4.4.274 | — |
| Linux | Linux Kernel | >= 4.5, < 4.9.274 | — |
| Linux | Linux Kernel | >= 4.10, < 4.14.238 | — |
| Linux | Linux Kernel | >= 4.15, < 4.19.196 | — |
| Linux | Linux Kernel | >= 4.20, < 5.4.128 | — |
| Linux | Linux Kernel | >= 5.5, < 5.10.46 | — |
| Linux | Linux Kernel | >= 5.11, < 5.12.13 | — |
| Linux | Linux Kernel | 5.13 | Rc1 |
References
Timeline
- Published
- Last Modified
- Status
- Modified
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