High severity · published Oct 26, 2021
CVE-2021-34586
In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests may cause a Null pointer dereference in the CODESYS web server and may result in a denial-of-service…
7.5
CVSS
13.7%
EPSS
No
On KEV
Description
In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests may cause a Null pointer dereference in the CODESYS web server and may result in a denial-of-service condition.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)13.7% · higher than 96% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
7F
750-8202 Firmware · Wago
before fw20 · source: NVD
7F
750-8203 Firmware · Wago
before fw20 · source: NVD
7F
750-8204 Firmware · Wago
before fw20 · source: NVD
7F
750-8206 Firmware · Wago
before fw20 · source: NVD
7F
750-8207 Firmware · Wago
before fw20 · source: NVD
7F
750-8208 Firmware · Wago
before fw20 · source: NVD
7F
750-8210 Firmware · Wago
before fw20 · source: NVD
7F
750-8211 Firmware · Wago
before fw20 · source: NVD
7F
750-8212 Firmware · Wago
before fw20 · source: NVD
7F
750-8213 Firmware · Wago
before fw20 · source: NVD
7F
750-8214 Firmware · Wago
before fw20 · source: NVD
7F
750-8216 Firmware · Wago
before fw20 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-34586
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-34586
Vendor Advisory
https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16876&token=a3f1d937f95e7034879f4f2ea8e5a99b168256a7&download=
Exploit
https://www.tenable.com/security/research/tra-2021-47
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