Security 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

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

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 Junk Data (T1001.001); 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

T1001.001 Junk Data Command And Control
Adversaries may add junk data to protocols used for command and control to make detection more difficult.
T1001.003 Protocol or Service Impersonation Command And Control
Adversaries may impersonate legitimate protocols or web service traffic to disguise command and control activity and thwart analysis efforts.
T1003.001 LSASS Memory Credential Access
Adversaries may attempt to access credential material stored in the process memory of the Local Security Authority Subsystem Service (LSASS).
T1003.007 Proc Filesystem Credential Access
Adversaries may gather credentials from the proc filesystem or `/proc`.
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
T1006 Direct Volume Access Stealth
Adversaries may directly access a volume to bypass file access controls and file system monitoring.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2019-15271Same vendor: Ciscoboth on KEV
CVE-2020-27131Same vendor: Cisco
CVE-2019-12630Same vendor: Cisco
CVE-2024-20253Same vendor: Cisco
CVE-2018-0125Same vendor: Ciscoboth on KEV
CVE-2018-15381Same vendor: Cisco
CVE-2009-2055Same vendor: Ciscoboth on KEV
CVE-2025-20393Same vendor: Ciscoboth on KEV
CVE-2017-12319Same vendor: Ciscoboth on KEV
CVE-2017-3881Same vendor: Ciscoboth on KEV

Affected Assets

cisco
secure access control system
5.2\(0.3\)

Mitigating Controls

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-02 none match
blocks

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.

removes
removes
removes
removes
removes

Hardening callouts derived

DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.

  • No fine-grained STIG row for CWE-20, a class-level weakness, and none of its children carries one either.

References