Root privilege escalation via unchecked 6pack decoding
Published Oct 4, 2021 · Updated Aug 4, 2024
Out-of-bounds write in the Linux kernel 6pack driver before 5.13.13 allows local users to gain root access through crafted input. decode_data() appends three decoded bytes to the 400-byte cooked_buf without bounding rx_count_cooked, so repeated malicious 6pack data writes past the slab allocation. A process must hold CAP_NET_ADMIN and reach the 6pack line discipline; successful exploitation can crash the kernel or execute code with root privileges.
Summary
What happened
Out-of-bounds write in the Linux kernel 6pack driver before 5.13.13 allows local users to gain root access through crafted input. decode_data() appends three decoded bytes to the 400-byte cooked_buf without bounding rx_count_cooked, so repeated malicious 6pack data writes past the slab allocation. A process must hold CAP_NET_ADMIN and reach the 6pack line discipline; successful exploitation can crash the kernel or execute code with root privileges.
The record
- CVE
- CVE-2021-42008
- Published
- Oct 4, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T1068
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Oct 4, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- Linux 6pack local privilege-escalation exploitfunctional · demonstrated
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Technologies
Your stack
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Your stack
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