CVE-2020-27821
CVE-2020-27821 is a medium-severity vulnerability in Qemu with a CVSS 3.x base score of 6.0. 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-787.
Key facts
- Severity: Medium (CVSS 3.x base score 6.0)
- CVSS v2: 2.1
- EPSS exploit prediction: 0% (28th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Qemu
- Published:
- Last modified:
Description
A flaw was found in the memory management API of QEMU during the initialization of a memory region cache. This issue could lead to an out-of-bounds write access to the MSI-X table while performing MMIO operations. A guest user may abuse this flaw to crash the QEMU process on the host, resulting in a denial of service. This flaw affects QEMU versions prior to 5.2.0.
Frequently asked questions
- What is CVE-2020-27821?
- A flaw was found in the memory management API of QEMU during the initialization of a memory region cache. This issue could lead to an out-of-bounds write access to the MSI-X table while performing MMIO operations. A guest user may abuse this flaw to crash the QEMU process on the host, resulting in a denial of service. This flaw affects QEMU versions prior to 5.2.0.
- How severe is CVE-2020-27821?
- CVE-2020-27821 has a CVSS 3.x base score of 6.0, 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-2020-27821 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-27821?
- CVE-2020-27821 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-2020-27821?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2020-27821 published?
- CVE-2020-27821 was published on 2020-12-08 and last updated on 2026-06-17.
References
- http://www.openwall.com/lists/oss-security/2020/12/16/6
- https://bugzilla.redhat.com/show_bug.cgi?id=1902651
- https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
- https://security.netapp.com/advisory/ntap-20210115-0006/
Affected products (2)
- cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
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