CVE-2021-45960

In Expat (aka libexpat) before 2.4.3, a left shift by 29 (or more) places in the storeAtts function in xmlparse.c can lead to realloc misbehavior (e.g., allocating too few bytes, or only freeing memory).

CVSS 3.1

8.8CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS

4.7% chance of exploitation in the next 30 days; higher than 91% of CVEs (scores of 2026-10-25)

CWE

CWE-682

Published

2022-01-01

Modified

2026-10-14

Record from

the NVD, synced 2026-10-19

Affected

• debian:debian_linux
• libexpat_project:libexpat
• netapp:active_iq_unified_manager
• netapp:hci_baseboard_management_controller
• netapp:oncommand_workflow_automation
• netapp:solidfire_\&_hci_management_node
• siemens:sinema_remote_connect_server
• tenable:nessus

References

• http://www.openwall.com/lists/oss-security/2022/01/17/3
• https://bugzilla.mozilla.org/show_bug.cgi?id=1217609
• https://cert-portal.siemens.com/productcert/pdf/ssa-484086.pdf
• https://github.com/libexpat/libexpat/issues/531
• https://github.com/libexpat/libexpat/pull/534

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