Local privilege escalation via iSCSI sysfs overflow
Published Mar 7, 2021 · Updated Aug 3, 2024
Heap buffer overflow in the Linux kernel through 5.11.3 allows local users to gain root privileges via oversized iSCSI Netlink attributes. iscsi_host_get_param() passes an attacker-controlled string to sprintf, which writes it into the single-page buffer backing the corresponding sysfs attribute without enforcing PAGE_SIZE. Exploitation requires a registered iSCSI transport and loadable supporting modules; successful attacks obtain root privileges, while unreliable attempts can crash the kernel.
Summary
What happened
Heap buffer overflow in the Linux kernel through 5.11.3 allows local users to gain root privileges via oversized iSCSI Netlink attributes. iscsi_host_get_param() passes an attacker-controlled string to sprintf, which writes it into the single-page buffer backing the corresponding sysfs attribute without enforcing PAGE_SIZE. Exploitation requires a registered iSCSI transport and loadable supporting modules; successful attacks obtain root privileges, while unreliable attempts can crash the kernel.
The record
- CVE
- CVE-2021-27365
- Published
- Mar 7, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T1068
- 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
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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
- GRIMM iSCSI local privilege-escalation PoCfunctional · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo