An infinite loop flaw was found in the e1000 NIC emulator of the QEMU. This issue occurs while processing transmits (tx) descriptors in process_tx_desc if various descriptor fields are initialized with invalid values. This flaw allows a guest to consume CPU cycles on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
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"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-20257.json"
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"2026-08-18T14:32:24Z"
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