What’s Vulnerable › Vulnerabilities

CVE-2021-28855

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-04-14 · updated 2026-06-17
• Weakness: CWE-476

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).

Affected products

• Entropymine Deark: before 1.5.8 — fixed in 1.5.8

How to fix

Upgrade to a fixed version: Entropymine Deark 1.5.8. Check the vendor advisory for mitigations.

References

• https://fatihhcelik.github.io/posts/NULL-Pointer-Dereference-Deark/
• https://github.com/fuzzing2026/CVE-PoCs/tree/main/deark-CVE-2021-28855
• https://github.com/jsummers/deark/commit/287f5ac31dfdc074669182f51ece637706070eeb
• https://fatihhcelik.github.io/posts/NULL-Pointer-Dereference-Deark/
• https://github.com/jsummers/deark/commit/287f5ac31dfdc074669182f51ece637706070eeb

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