Medium
Security advisory
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-20257
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 09:25 UTC · Revision 1
Source evidence
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.
osv:CVE-2021-20257
Complete source record
{
"id": "fc1ca7db179d062d90e99753c5821f91ed7f6026b74ecca8a99972cb4bdbb754",
"url": "https://osv.dev/vulnerability/CVE-2021-20257",
"method": "structured",
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"evidence": "osv:CVE-2021-20257",
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},
{
"last_affected": "13.0"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2021-20257",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 443660,
"published_at": "2022-03-16T15:15:09.983+00:00"
}