Is CVE-2021-45960 being actively exploited?

CVE-2021-45960 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2021-45960?

CVE-2021-45960 has a CVSS 3.1 base score of 8.8 (HIGH).

CVE-2021-45960

HIGH · CVSS 8.8EPSS 4.3%EU EUVD

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).

Key facts

CVSS score: 8.8 (v3.1)
Severity: HIGH
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-682
EPSS score: 4.3% (91th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2021-32666)
Published: January 1, 2022
NVD last modified: October 14, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2021-32666 in the EU Vulnerability Database. Last updated in EUVD on October 14, 2026.

View on the EU Vulnerability Database

Affected products

debian / debian linux
debian / debian linux
libexpat project / libexpat
netapp / active iq unified manager
netapp / hci baseboard management controller
netapp / hci baseboard management controller
netapp / hci baseboard management controller
netapp / oncommand workflow automation
netapp / solidfire & hci management node
siemens / sinema remote connect server
tenable / nessus

Certified products that may be affected

2 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

Nessus Manager 8.11.1 - Tenable, Inc. - Common Criteria CCEVS-VR-VID-11067-2020 - archived
Tenable SecurityCenter 4.4 (SC) and Components: 3D Tool 2.0.1 Log Correlation Engine 3.6 (LCE), Passive Vulnerability Scanner 3.6 (PVS), Nessus 5.0.1, and xTool 2.1 - Tenable Network Security, Inc. - Common Criteria CCEVS-VR-VID-10443-2012 - archived

References

http://www.openwall.com/lists/oss-security/2022/01/17/3(Exploit, Mailing List, Third Party Advisory)
https://bugzilla.mozilla.org/show_bug.cgi?id=1217609(Issue Tracking, Permissions Required, Third Party Advisory)
https://cert-portal.siemens.com/productcert/html/ssa-398330.html
https://cert-portal.siemens.com/productcert/html/ssa-484086.html
https://cert-portal.siemens.com/productcert/pdf/ssa-484086.pdf(Patch, Third Party Advisory)
https://github.com/libexpat/libexpat/issues/531(Exploit, Issue Tracking, Patch, Third Party Advisory)
https://github.com/libexpat/libexpat/pull/534(Patch, Third Party Advisory)
https://security.gentoo.org/glsa/202209-24(Third Party Advisory)
https://security.netapp.com/advisory/ntap-20220121-0004/(Third Party Advisory)
https://www.debian.org/security/2022/dsa-5073(Issue Tracking, Third Party Advisory)
https://www.tenable.com/security/tns-2022-05(Third Party Advisory)

Last updated October 16, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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