CVE-2026-8463

Crypt::Argon2 versions from 0.017 before 0.031 for Perl perform a heap out-of-bounds read in argon2_verify on empty encoded input. The auto-detect form of argon2_verify passes encoded_len - 1 as the length argument to memchr without checking that encoded_len is non-zero. When the encoded string is empty, the size_t subtraction underflows to SIZE_MAX and memchr scans adjacent heap memory looking for a '$' separator byte. A caller that invokes argon2_verify against a stored hash that may legitimately be empty (for example a placeholder row or a NULL column materialised as an empty string) reads out-of-bounds heap memory, which can crash the process or leak the position of an adjacent '$' byte into subsequent parsing.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/Leont/crypt-argon2/commit/92eac03ce63d541e0ead7ea5a89b9b67ce0c0e64.patch	Patch
https://metacpan.org/release/LEONT/Crypt-Argon2-0.031/changes	Release Notes
http://www.openwall.com/lists/oss-security/2026/05/13/4	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:leont:crypt\:\:argon2:*:*:*:*:*:perl:*:*

History

No history.

Information

Published : 2026-05-13 14:18

Updated : 2026-06-17 11:03

NVD link : CVE-2026-8463

Mitre link : CVE-2026-8463

CVE.ORG link : CVE-2026-8463

JSON object : View

Products Affected

leont

crypt\

CWE

CWE-126

Buffer Over-read

CWE-191

Integer Underflow (Wrap or Wraparound)

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