High severity · published Jan 1, 2022
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,…
8.8
CVSS
4.7%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)4.7% · higher than 92% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AI
Active IQ Unified Manager · Netapp
All versions, or not specified · source: NVD
DL
Debian Linux · Debian
10.0; 11.0 · source: NVD
HB
Hci Baseboard Management Controller · Netapp
h610c; h610s; h615c · source: NVD
LI
Libexpat · Libexpat Project
before 2.4.3 · source: NVD
NE
Nessus · Tenable
before 8.15.3; 10.0.0 before 10.1.1 · source: NVD
OW
Oncommand Workflow Automation · Netapp
All versions, or not specified · source: NVD
SR
Sinema Remote Connect Server · Siemens
before 3.1 · source: NVD
SH
Solidfire & Hci Management Node · Netapp
All versions, or not specified · source: NVD
SS
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.0 before V3.1.5; V3.1.0 before V3.1.5 · source: CISA
SS
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens
V3.1.0 before V3.1.5; V3.1.0 before V3.1.5 · source: CISA
SS
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.0 before V3.1.5 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-45960
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-45960
Exploit
http://www.openwall.com/lists/oss-security/2022/01/17/3
Issue Tracking
https://bugzilla.mozilla.org/show_bug.cgi?id=1217609
Patch
https://cert-portal.siemens.com/productcert/pdf/ssa-484086.pdf
Exploit
https://github.com/libexpat/libexpat/issues/531
Patch
https://github.com/libexpat/libexpat/pull/534
Third Party Advisory
https://security.gentoo.org/glsa/202209-24
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