Cyber Resilience

CVE-2018-0147

RCE in Cisco Secure Access Control System 5.2\(0.3\)

CISA KEVActive ExploitationEUVD ExploitedRCEDeserialization
Published
08 March 2018
Modified
14 January 2026
KEV Added
25 March 2022
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.18 97th percentile
Risk Priority 97 floored blend · peak EPSS

Summary

CVE-2018-0147 is a critical-severity Improper Input Validation (CWE-20) vulnerability in Cisco Secure Access Control System. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 3% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

A vulnerability in Java deserialization affects Cisco Secure Access Control System (ACS) versions prior to 5.8 patch 9. The issue stems from insecure handling of user-supplied serialized objects, tracked under Cisco Bug ID CSCvh25988 and assigned CWE-20 and CWE-502. It carries a CVSS 3.1 base score of 9.8, reflecting network-accessible attack complexity with no required credentials or user interaction.

An unauthenticated remote attacker can exploit the flaw by sending a crafted serialized Java object to the affected ACS instance. Successful exploitation grants the ability to execute arbitrary commands on the device with root privileges.

The referenced Cisco Security Advisory at https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180307-acs2 addresses the issue and identifies the availability of release 5.8 patch 9 as the corrective update. Additional details appear in the associated SecurityFocus and SecurityTracker entries.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A vulnerability in Java deserialization used by Cisco Secure Access Control System (ACS) prior to release 5.8 patch 9 could allow an unauthenticated, remote attacker to execute arbitrary commands on an affected device. The vulnerability is due to insecure deserialization…

more

of user-supplied content by the affected software. An attacker could exploit this vulnerability by sending a crafted serialized Java object. An exploit could allow the attacker to execute arbitrary commands on the device with root privileges. Cisco Bug IDs: CSCvh25988.

CWE(s)
KEV Date Added
25 March 2022

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1036.001 Invalid Code Signature Stealth
Adversaries may attempt to mimic features of valid code signatures to increase the chance of deceiving a user, analyst, or tool.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2017-12234Same vendor: Ciscoboth on KEV
CVE-2017-3881Same vendor: Ciscoboth on KEV
CVE-2017-12235Same vendor: Ciscoboth on KEV
CVE-2018-0159Same vendor: Ciscoboth on KEV
CVE-2018-0125Same vendor: Ciscoboth on KEV
CVE-2017-12233Same vendor: Ciscoboth on KEV
CVE-2009-2055Same vendor: Ciscoboth on KEV
CVE-2017-12319Same vendor: Ciscoboth on KEV
CVE-2020-3161Same vendor: Ciscoboth on KEV
CVE-2018-0156Same vendor: Ciscoboth on KEV

Affected Assets

cisco
secure access control system
5.2\(0.3\)

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-20 CWE-502

Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.

addresses: CWE-20 CWE-502

Directly implements checks on information inputs to reject invalid data before processing.

addresses: CWE-502

Penetration testing supplies malicious serialized objects, detecting unsafe deserialization and supporting corrective actions.

addresses: CWE-20

Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.

addresses: CWE-502

Untrusted serialized data can be deserialized and observed inside the chamber, blocking gadget-chain exploitation outside the sandbox.

addresses: CWE-502

Identifies and blocks malicious code introduced through deserialization of untrusted data at system boundaries.

addresses: CWE-502

Integrity verification of serialized information can detect tampering before deserialization occurs.

addresses: CWE-20

Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require and enforce input validation during development.

PR.PS-02 none match
prevents

PR.PS-02 addresses only post-deployment updates/patching and cannot prevent introduction of unsafe deserialization code, yet it can remediate some instances when the flaw exists in outdated libraries or components.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Testing against a defined set of requirements and using code review plus vulnerability scanning forces validation of inputs and handling of unanticipated conditions, reducing the chance that malformed data will be accepted.

prevents

Secure-coding guidelines and mandatory security testing (including code scans) compel developers to validate and sanitize inputs at design and implementation time, lowering the incidence of malformed or malicious data reaching downstream components.

prevents

Mandating input controls that include integrity checks and input validation ensures that untrusted data is examined before use, blocking the root cause of many injection and malformed-data weaknesses.

prevents

Security-by-design principles explicitly call for data validation and sanitization at every layer, reducing the chance that malformed or malicious input will be processed without scrutiny.

prevents

Requiring language-specific secure coding standards, peer review, SAST and documented mitigation of common programming errors forces validation of all inputs before they are trusted.

finds

Regular scanning of third-party libraries and timely patching reduce the likelihood that unsafe deserialization vulnerabilities remain active.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

RHEL 8 (1 rule)
  • V-230265 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-20

References