CVE-2021-27365 Memory corruption in n/a

What is CVE-2021-27365?

CVE-2021-27365 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 7 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

An issue was discovered in the Linux kernel through 5.11.3. Certain iSCSI data structures do not have appropriate length constraints or checks, and can exceed the PAGE_SIZE value. An unprivileged user can send a Netlink message that is associated with iSCSI, and has a length up to the maximum length of a Netlink message.

Weakness: CWE-787

Which versions are affected by CVE-2021-27365?

It affects 5 products.

Products include Debian Debian Linux, Linux kernel, Netapp Cloud Backup, Netapp Solidfire Baseboard Management Controller Firmware, Oracle Tekelec Platform Distribution.

How do I fix CVE-2021-27365?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-27365 being exploited?

There is no known exploitation of CVE-2021-27365 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

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• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-6534, DEBIAN-CVE-2021-27365, GHSA-qwp9-8pwv-6hg4, UBUNTU-CVE-2021-27365.