CVE-2021-47245 (GCVE-0-2021-47245)

Vulnerability from cvelistv5 – Published: 2024-05-21 14:19 – Updated: 2025-05-04 07:07
VLAI?
Title
netfilter: synproxy: Fix out of bounds when parsing TCP options
Summary
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.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 48b1de4c110a7afa4b85862f6c75af817db26fad , < e1eb98cfeafdd85537e7e3cefe93ca9bfbcc3ea8 (git)
Affected: 48b1de4c110a7afa4b85862f6c75af817db26fad , < 576c1526b4d83c44ad7b673cb841f36cbc6cb6c4 (git)
Affected: 48b1de4c110a7afa4b85862f6c75af817db26fad , < 674b5f0c6a4fc5d3abce877048290cea6091fcb1 (git)
Affected: 48b1de4c110a7afa4b85862f6c75af817db26fad , < 7d9a9a1a88a3da574e019b4de756bc73337b3b0b (git)
Affected: 48b1de4c110a7afa4b85862f6c75af817db26fad , < 6defc77d48eff74075b80ad5925061b2fc010d98 (git)
Affected: 48b1de4c110a7afa4b85862f6c75af817db26fad , < 9cdf299ba4e153b5e56187648420de22c6216f02 (git)
Affected: 48b1de4c110a7afa4b85862f6c75af817db26fad , < f648089337cb8ed40b2bb96e244f72b9d97dc96b (git)
Affected: 48b1de4c110a7afa4b85862f6c75af817db26fad , < 5fc177ab759418c9537433e63301096e733fb915 (git)
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    Linux Linux Affected: 3.12
Unaffected: 0 , < 3.12 (semver)
Unaffected: 4.4.274 , ≤ 4.4.* (semver)
Unaffected: 4.9.274 , ≤ 4.9.* (semver)
Unaffected: 4.14.238 , ≤ 4.14.* (semver)
Unaffected: 4.19.196 , ≤ 4.19.* (semver)
Unaffected: 5.4.128 , ≤ 5.4.* (semver)
Unaffected: 5.10.46 , ≤ 5.10.* (semver)
Unaffected: 5.12.13 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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