How severe is CVE-2016-7421?

CVE-2016-7421 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2016-7421 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-7421?

CVE-2016-7421 primarily affects Qemu. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-7421?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2016-7421 published?

CVE-2016-7421 was published on 2016-12-10 and last updated on 2026-06-17.

CVE-2016-7421

CVE-2016-7421 is a medium-severity vulnerability in Qemu with a CVSS 3.x base score of 4.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-834.

Key facts

Severity: Medium (CVSS 3.x base score 4.4)
CVSS v2: 2.1
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-834
Affected product: Qemu
Published: 2016-12-10
Last modified: 2026-06-17

Description

The pvscsi_ring_pop_req_descr function in hw/scsi/vmw_pvscsi.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) by leveraging failure to limit process IO loop to the ring size.

Frequently asked questions

What is CVE-2016-7421?: The pvscsi_ring_pop_req_descr function in hw/scsi/vmw_pvscsi.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) by leveraging failure to limit process IO loop to the ring size.
How severe is CVE-2016-7421?: CVE-2016-7421 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2016-7421 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-7421?: CVE-2016-7421 primarily affects Qemu. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-7421?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-7421 published?: CVE-2016-7421 was published on 2016-12-10 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

More vulnerabilities in Qemu

CVE-2022-36648 — Critical (CVSS 10.0): The hardware emulation in the of_dpa_cmd_add_l2_flood of rocker device model in QEMU, as used in 7.0.0 and earlier,…
CVE-2017-16845 — Critical (CVSS 10.0): hw/input/ps2.c in Qemu does not validate 'rptr' and 'count' values during guest migration, leading to out-of-bounds…
CVE-2015-8556 — Critical (CVSS 10.0): Local privilege escalation vulnerability in the Gentoo QEMU package before 2.5.0-r1.
CVE-2009-3616 — Critical (CVSS 9.9): Multiple use-after-free vulnerabilities in vnc.c in the VNC server in QEMU 0.10.6 and earlier might allow guest OS…
CVE-2019-12929 — Critical (CVSS 9.8): The QMP guest_exec command in QEMU 4.0.0 and earlier is prone to OS command injection, which allows the attacker to…
CVE-2019-12928 — Critical (CVSS 9.8): The QMP migrate command in QEMU version 4.0.0 and earlier is vulnerable to OS command injection, which allows the…

All CVEs affecting Qemu →

Other CWE-834 (Excessive Iteration) vulnerabilities

CVE-2017-12587 — High (CVSS 8.8): ImageMagick 7.0.6-1 has a large loop vulnerability in the ReadPWPImage function in coders\pwp.c.
CVE-2025-62707 — High (CVSS 7.5): pypdf is a free and open-source pure-python PDF library. Prior to version 6.1.3, an attacker who uses this…
CVE-2025-56571 — High (CVSS 7.5): Finance.js v4.1.0 contains a Denial of Service (DoS) vulnerability via the IRR function’s depth parameter. Improper…
CVE-2024-4227 — High (CVSS 7.5): In Genivia gSOAP with a specific configuration an unauthenticated remote attacker can generate a high CPU load when…
CVE-2023-49316 — High (CVSS 7.5): In Math/BinaryField.php in phpseclib 3 before 3.0.34, excessively large degrees can lead to a denial of service.
CVE-2023-5632 — High (CVSS 7.5): In Eclipse Mosquito before and including 2.0.5, establishing a connection to the mosquitto server without sending data…

Browse all CWE-834 (Excessive Iteration) vulnerabilities →