How severe is CVE-2021-28021?

CVE-2021-28021 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-28021 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-28021?

CVE-2021-28021 primarily affects Stb Project Stb. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-28021?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-28021 published?

CVE-2021-28021 was published on 2021-10-15 and last updated on 2026-06-17.

CVE-2021-28021

CVE-2021-28021 is a high-severity vulnerability in Stb Project Stb with a CVSS 3.x base score of 7.8. 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: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Stb Project Stb
Published: 2021-10-15
Last modified: 2026-06-17

Description

Buffer overflow vulnerability in function stbi__extend_receive in stb_image.h in stb 2.26 via a crafted JPEG file.

Frequently asked questions

What is CVE-2021-28021?: Buffer overflow vulnerability in function stbi__extend_receive in stb_image.h in stb 2.26 via a crafted JPEG file.
How severe is CVE-2021-28021?: CVE-2021-28021 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-28021 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-28021?: CVE-2021-28021 primarily affects Stb Project Stb. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-28021?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-28021 published?: CVE-2021-28021 was published on 2021-10-15 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:stb_project:stb:2.26:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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