CVE-2021-28855

Published: Apr 14, 2021Updated: Jan 26, 2026 Sources: CVE List NVDCWE-476

NVD MITRE

5.5CVSSMEDIUM

EPSS Score

Description

In Deark before 1.5.8, a specially crafted input file can cause a NULL pointer dereference in the dbuf_write function (src/deark-dbuf.c).

CVSS Vector Breakdown

Exploitability

AV:LAttack Vector

Local

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:RUser Interaction

Required

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-476

Affected Products

n/a n/a

deark entropymine

Attack Graph

Products CVE Techniques Tactics

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Exploitability

1 exploit source identified

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Official Patch Available

MITRE ATT&CK

2 techniques

Impact

Initial Access

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References

https://fatihhcelik.github.io/posts/NULL-Pointer-Dereference-Deark/

fatihhcelik.github.io

https://github.com/jsummers/deark/commit/287f5ac31dfdc074669182f51ece637706070eeb

github.com

https://github.com/fuzzing2026/CVE-PoCs/tree/main/deark-CVE-2021-28855

github.com

Timeline

Published

Apr 14, 2021

Last Updated

Jan 26, 2026

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