Kernel memory disclosure via unchecked Netlink lengths
Published Mar 7, 2021 · Updated Aug 3, 2024
Out-of-bounds read in the Linux kernel 5.11.3 and earlier allows local users to disclose kernel memory or crash the system via Netlink messages. In iscsi_if_recv_msg, the send_pdu path trusts user-controlled header and data lengths without checking the received buffer, permitting an 8,192-byte read at a controlled 32-bit offset. Unprivileged local access can reach the flaw; disclosure depends on a later iSCSI send operation, while the published demonstration uses an intentionally invalid offset to trigger a kernel panic.
Summary
What happened
Out-of-bounds read in the Linux kernel 5.11.3 and earlier allows local users to disclose kernel memory or crash the system via Netlink messages. In iscsi_if_recv_msg, the send_pdu path trusts user-controlled header and data lengths without checking the received buffer, permitting an 8,192-byte read at a controlled 32-bit offset. Unprivileged local access can reach the flaw; disclosure depends on a later iSCSI send operation, while the published demonstration uses an intentionally invalid offset to trigger a kernel panic.
The record
- CVE
- CVE-2021-27364
- Published
- Mar 7, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-125, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 7, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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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.
Weakness, pattern, technique
Public exploit references
- send_pdu_oob proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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