CVE-2026-27171

zlib before 1.3.2 allows CPU consumption via crc32_combine64 and crc32_combine_gen64 because x2nmodp can do right shifts within a loop that has no termination condition.

CVSS v3 2.9 LOW

2.9^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.4 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://7asecurity.com/blog/2026/02/zlib-7asecurity-audit/	Product
https://7asecurity.com/reports/pentest-report-zlib-RC1.1.pdf	Technical Description
https://github.com/madler/zlib/issues/904	Exploit Issue Tracking
https://github.com/madler/zlib/releases/tag/v1.3.2	Release Notes
https://ostif.org/zlib-audit-complete/	Product
https://7asecurity.com/reports/pentest-report-zlib-RC1.1.pdf	Technical Description

Configurations

Configuration 1 (hide)

cpe:2.3:a:zlib:zlib:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-02-18 04:16

Updated : 2026-03-25 21:27

NVD link : CVE-2026-27171

Mitre link : CVE-2026-27171

CVE.ORG link : CVE-2026-27171

JSON object : View

Products Affected

zlib

zlib

CWE

CWE-1284

Improper Validation of Specified Quantity in Input

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