The vulnerabilities of the functions crc32_combine64 and crc32_combine_gen64 in the open-source data compression library zlib allow a hacker to cause a service failure.

🗓️ 13 May 2026 00:00:00Reported by FSTEC of Russia — Information Security Threat DatabaseType

bdu_fstec

bdu_fstec🔗 bdu.fstec.ru👁 1 Views

Vulnerabilities in crc32_combine64 and crc32_combine_gen64 in zlib allow disruption from an unbounded x2nmodp loop.

Reporter	Title	Published	Views	Family All 104
IBM Security Bulletins	Security Bulletin: IBM i is Affected by an Improper Validation Vulnerability in zlib [CVE-2026-27171]	22 May 202602:07	–	ibm
IBM Security Bulletins	Security Bulletin: IBM WinCollect Agent is vulnerable to using components with known vulnerabilities	6 Jul 202613:49	–	ibm
IBM Security Bulletins	Security Bulletin: IBM MQ for HPE NonStop is vulnerable to an issue in zlib (CVE-2026-27171)	1 Jul 202621:59	–	ibm
IBM Security Bulletins	Security Bulletin: Due to the use of zlib, IBM EntireX is vulnerable to Improper Validation of Specified Quantity in Input vulnerabilities (CVE-2026-3381, CVE-2026-27171).	19 Jun 202607:52	–	ibm
IBM Security Bulletins	Security Bulletin: A vulnerability in zlib affects IBM License Metric Tool v9 scanner (CIT)	26 Mar 202611:43	–	ibm
IBM Security Bulletins	Security Bulletin: Vulnerabilities Addressed in IBM Tivoli Network Manager IP Edition (ITNM) version 4.2 Fix Pack 24 (4.2.0.24)	9 Apr 202610:21	–	ibm
IBM Security Bulletins	Security Bulletin: IBM Quantum Safe Remediator is affected by multiple vulnerabilities	5 May 202615:14	–	ibm
ATTACKERKB	CVE-2026-27171	18 Feb 202602:36	–	attackerkb
ATTACKERKB	CVE-2026-3381	5 Mar 202601:28	–	attackerkb
ATTACKERKB	CVE-2026-4176	29 Mar 202620:50	–	attackerkb

Vulners

Node

red_hat red_hat_build_of_openjdkMatch17

OR

red_hat red_hat_build_of_openjdkMatch1.8

OR

red_hat red_hat_openshift_container_platformMatch4

OR

red_hat red_hat_build_of_openjdkMatch21

OR

red_hat red_hat_build_of_openjdkMatch25

OR

red_hat red_hat_enterprise_linuxMatch7

OR

red_hat red_hat_enterprise_linuxMatch8

OR

red_hat red_hat_enterprise_linuxMatch9

OR

red_hat red_hat_enterprise_linuxMatch10

Source	Link
7asecurity	www.7asecurity.com/blog/2026/02/zlib-7asecurity-audit/
7asecurity	www.7asecurity.com/reports/pentest-report-zlib-RC1.1.pdf
github	www.github.com/madler/zlib/issues/904
github	www.github.com/madler/zlib/releases/tag/v1.3.2
dbugs	www.dbugs.ptsecurity.com/vulnerability/PT-2026-20360
ostif	www.ostif.org/zlib-audit-complete/
security-tracker	www.security-tracker.debian.org/tracker/CVE-2026-27171
access	www.access.redhat.com/security/cve/cve-2026-27171
redos	www.redos.red-soft.ru/search/
web	www.web.nvd.nist.gov/view/vuln/detail

28 May 2026 00:00Current

5.8Medium risk

Vulners AI Score5.8

CVSS 24.6

CVSS 35.5

EPSS0.00204

crc32 combine64 crc32 combine gen64 zlib library x2nmodp service disruption