Home/CVE/An infinite loop flaw was found in the e1000 NIC emulator of the QEMU. This issue occurs while processing transmits (tx)
CVE

CVE-2021-20257

An infinite loop flaw was found in the e1000 NIC emulator of the QEMU. This issue occurs while processing transmits (tx)

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.

MEDIUM · CVSS 6.5 EPSS 0.0008
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules1 YARA rules0
⬡

Weakness Classification

CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')
CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')
▤

Affected Products & Versions

6
qemu< 6.2.0
fedoraproject fedoraall versions
redhat openstack platformall versions
redhat enterprise linuxall versions
redhat codeready linux builderall versions
debian linuxall versions
◈

Sigma Hunt Rules

1
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
productmediumPotentially Suspicious Usage Of Qemu
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · secalert@redhat.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD16 Mar 2022 · 03:15 PM
CVSS VectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
⚑

Vendor Advisories

28
suse-csafopenSUSE-SU-2024:11287-1
msrcCVE-2021-20257
suse-csafSUSE-SU-2022:1375-1
usnUSN-5010-1
suse-csafopenSUSE-SU-2021:1043-1
🔗

References & Sources

7
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://bugzilla.redhat.com/show_bug.cgi?id=1930087Issue TrackingPatchThird Party Advisory
https://github.com/qemu/qemu/commit/3de46e6fc489c52c9431a8a832ad8170a7569bd8PatchThird Party Advisory
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlMailing ListThird Party Advisory
https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg07428.htmlMailing ListPatchVendor Advisory
https://security.gentoo.org/glsa/202208-27Third Party Advisory
https://security.netapp.com/advisory/ntap-20220425-0003/Third Party Advisory
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