CVE-2026-81721Network attack vectorHinoki check available

Process crash via unbounded KDF memory allocation

Published Aug 27, 2026 · Updated Aug 27, 2026

Uncontrolled resource consumption in OpenSSL Encrypt before 1.4.9 allows attackers to crash the process via crafted encrypted files. The encrypted-file and keystore-header parsers accept attacker-declared Argon2, scrypt, or Balloon cost values and allocate memory without a ceiling. Processing an attacker-controlled file requires no authentication and can exhaust host memory before cryptographic verification.

CVSS severity8.7
High
EPSS probability0.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Uncontrolled resource consumption in OpenSSL Encrypt before 1.4.9 allows attackers to crash the process via crafted encrypted files. The encrypted-file and keystore-header parsers accept attacker-declared Argon2, scrypt, or Balloon cost values and allocate memory without a ceiling. Processing an attacker-controlled file requires no authentication and can exhaust host memory before cryptographic verification.

The record

CVE
CVE-2026-81721
Published
Aug 27, 2026
Updated
Aug 27, 2026
Vendor
jahlives
Product
OpenSSL Encrypt
Classifications
CWE-400, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=0 <1.4.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

jahlives · OpenSSL Encryptversion=0 <1.4.9

Published CVSS scores

8.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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