How severe is CVE-2021-36977?

CVE-2021-36977 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-36977 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-36977?

CVE-2021-36977 primarily affects Matio Project Matio. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-36977?

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

When was CVE-2021-36977 published?

CVE-2021-36977 was published on 2021-07-20 and last updated on 2026-06-17.

CVE-2021-36977

CVE-2021-36977 is a medium-severity vulnerability in Matio Project Matio with a CVSS 3.x base score of 6.5. 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 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 2% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Matio Project Matio
Published: 2021-07-20
Last modified: 2026-06-17

Description

matio (aka MAT File I/O Library) 1.5.20 and 1.5.21 has a heap-based buffer overflow in H5MM_memcpy (called from H5MM_malloc and H5C_load_entry), related to use of HDF5 1.12.0.

Frequently asked questions

What is CVE-2021-36977?: matio (aka MAT File I/O Library) 1.5.20 and 1.5.21 has a heap-based buffer overflow in H5MM_memcpy (called from H5MM_malloc and H5C_load_entry), related to use of HDF5 1.12.0.
How severe is CVE-2021-36977?: CVE-2021-36977 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-36977 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36977?: CVE-2021-36977 primarily affects Matio Project Matio. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-36977?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-36977 published?: CVE-2021-36977 was published on 2021-07-20 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:matio_project:matio:1.5.20:*:*:*:*:*:*:*
cpe:2.3:a:matio_project:matio:1.5.21:*:*:*:*:*:*:*

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