How severe is CVE-2021-21833?

CVE-2021-21833 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-21833 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21833?

CVE-2021-21833 affects Accusoft Imagegear. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-21833?

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

When was CVE-2021-21833 published?

CVE-2021-21833 was published on 2021-06-11 and last updated on 2026-06-17.

CVE-2021-21833

CVE-2021-21833 is a critical-severity vulnerability in Accusoft Imagegear with a CVSS 3.x base score of 9.8. 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-129.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-129
Affected product: Accusoft Imagegear
Published: 2021-06-11
Last modified: 2026-06-17

Description

An improper array index validation vulnerability exists in the TIF IP_planar_raster_unpack functionality of Accusoft ImageGear 19.9. A specially crafted malformed file can lead to an out-of-bounds write. An attacker can provide a malicious file to trigger this vulnerability.

Frequently asked questions

What is CVE-2021-21833?: An improper array index validation vulnerability exists in the TIF IP_planar_raster_unpack functionality of Accusoft ImageGear 19.9. A specially crafted malformed file can lead to an out-of-bounds write. An attacker can provide a malicious file to trigger this vulnerability.
How severe is CVE-2021-21833?: CVE-2021-21833 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-21833 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21833?: CVE-2021-21833 affects Accusoft Imagegear. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-21833?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-21833 published?: CVE-2021-21833 was published on 2021-06-11 and last updated on 2026-06-17.

References

https://talosintelligence.com/vulnerability_reports/TALOS-2021-1296

Affected products (1)

cpe:2.3:a:accusoft:imagegear:19.9:*:*:*:*:*:*:*

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