Cyber Resilience

CVE-2021-3409

Medium

Published: 23 March 2021

Published
23 March 2021
Modified
21 November 2024
KEV Added
Patch
09 March 2021
CVSS Score v3.1 5.7 CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:L
EPSS Score 0.0031 54.2th percentile
Risk Priority 12 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-3409 is a medium-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Qemu Qemu. Its CVSS base score is 5.7 (Medium).

Operationally, ranked in the top 45.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

The patch for CVE-2020-17380/CVE-2020-25085 was found to be ineffective, thus making QEMU vulnerable to the out-of-bounds read/write access issues previously found in the SDHCI controller emulation code. This flaw allows a malicious privileged guest to crash the QEMU process on…

more

the host, resulting in a denial of service or potential code execution. QEMU up to (including) 5.2.0 is affected by this.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

qemu
qemu
≤ 5.2.0
redhat
enterprise linux
7.0
fedoraproject
fedora
33
debian
debian linux
9.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-119

Ongoing control assessments and code testing (static/dynamic analysis, fuzzing) surface memory buffer restriction failures, which are then remediated before release.

addresses: CWE-119

Managed runtimes used by platform-independent applications (e.g., JVM, CLR) enforce memory safety, preventing most buffer overflows that require direct memory manipulation.

addresses: CWE-119

Memory protections (e.g., W^X, ASLR) make exploitation of buffer-boundary violations far harder to turn into code execution.

addresses: CWE-119

Detects exploitation attempts that produce memory corruption, crashes, or anomalous behavior.

References