imPC@ndo IT

Tracker / CVE-2021-47245

CVE-2021-47245

High 8.2

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.

Affected products and versions

linux linux_kernel
linux linux_kernel · 3.12 → 4.4.274
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 · 4.5 → 4.9.274
linux linux_kernel · 5.11 → 5.12.13
linux linux_kernel · 5.5 → 5.10.46

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References