Cisco Security Manager Java Deserialization Vulnerabilities

published 2020-11-17 5y ago modified 2026-06-17 4mo ago also EUVD-2020-19655

cvss: 8.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 91.8%; EPSS 91.8% chance of exploitation in 30 days, percentile 99.8%
public exploits: 0; none known

Multiple vulnerabilities in the Java deserialization function that is used by Cisco Security Manager could allow an unauthenticated, remote attacker to execute arbitrary commands on an affected device. These vulnerabilities are due to insecure deserialization of user-supplied content by the affected software. An attacker could exploit these vulnerabilities by sending a malicious serialized Java object to a specific listener on an affected system. A successful exploit could allow the attacker to execute arbitrary commands on the device with the privileges of NT AUTHORITY\SYSTEM on the Windows target host. Cisco has not released software updates that address these vulnerabilities.

Is CVE-2020-27131 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: last yr. (2024-11-13)

Exploit prediction

91.79% chance of exploitation in the next 30 days, higher than 99.8% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	10.0	AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected products

Cisco Cisco Security Manager

Classification

Weakness

CWE-20 Improper Input Validation
CWE-502 Deserialization of Untrusted Data

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-csm-java-rce-mWJEedcD
vendor-advisory

Sources

CVE List CVE-2020-27131
NVD CVE-2020-27131

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.