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CVE-2021-41991

Published: Oct 18, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDU csafCWE-190
7.5HIGH
NVD MITRE
EPSS Score
4.8%
Top 8.8%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

The in-memory certificate cache in strongSwan before 5.9.4 has a remote integer overflow upon receiving many requests with different certificates to fill the cache and later trigger the replacement of cache entries. The code attempts to select a less-often-used cache entry by means of a random number generator, but this is not done correctly. Remote code execution might be a slight possibility.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-190

Affected Products

Siemens AG
commercial·DEaka siemens
RUGGEDCOM RM1224 LTE(4G) EU
ICS / OT / IoT
RUGGEDCOM RM1224 LTE(4G) NAM
ICS / OT / IoT
SCALANCE M804PB
ICS / OT / IoT
SCALANCE M812-1 ADSL-Router
ICS / OT / IoT
SCALANCE M816-1 ADSL-Router
ICS / OT / IoT
SCALANCE M826-2 SHDSL-Router
ICS / OT / IoT
SCALANCE M874-2
ICS / OT / IoT
SCALANCE M874-3
ICS / OT / IoT
Сообщество свободного программного обеспечения
oss-projectaka fsf
Debian GNU/LinuxOn-premOS
Operating Systems / linux-distro
strongSwan
Security Products / secure-gateway-vpn
Canonical Ltd.
commercial·GBaka canonical
UbuntuOn-premOS
Operating Systems / linux-distro
Fedora Project
oss-project·USaka fedora
FedoraOn-premOS
Operating Systems / linux-distro
АО «ИВК»
commercial·RUaka ivk
Альт 8 СПOn-premOS
Operating Systems / linux-distro
АО «НППКТ»
commercial·RU
ОСОН ОСнова ОnyxOn-premOS
Operating Systems / linux-distro
and 49 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Initial Access
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References

https://github.com/strongswan/strongswan/releases/tag/5.9.4
github.com
https://www.strongswan.org/blog/2021/10/18/strongswan-vulnerability-%28cve-2021-41991%29.html
strongswan.org
https://www.debian.org/security/2021/dsa-4989
debian.org
and 20 more references View all →

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