How severe is CVE-2021-33656?

CVE-2021-33656 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over physical access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33656 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33656?

CVE-2021-33656 primarily affects Openatom Openeuler. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33656?

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

When was CVE-2021-33656 published?

CVE-2021-33656 was published on 2022-07-18 and last updated on 2026-06-17.

CVE-2021-33656

CVE-2021-33656 is a medium-severity vulnerability in Openatom Openeuler with a CVSS 3.x base score of 6.8. 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 6.8)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Openatom Openeuler
Published: 2022-07-18
Last modified: 2026-06-17

Description

When setting font with malicous data by ioctl cmd PIO_FONT,kernel will write memory out of bounds.

Frequently asked questions

What is CVE-2021-33656?: When setting font with malicous data by ioctl cmd PIO_FONT,kernel will write memory out of bounds.
How severe is CVE-2021-33656?: CVE-2021-33656 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over physical access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33656 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33656?: CVE-2021-33656 primarily affects Openatom Openeuler. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33656?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-33656 published?: CVE-2021-33656 was published on 2022-07-18 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:o:openatom:openeuler:20.03:-:*:*:lts:*:*:*
cpe:2.3:o:openatom:openeuler:20.03:sp1:*:*:lts:*:*:*
cpe:2.3:o:openatom:openeuler:20.03:sp3:*:*:lts:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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