A vulnerability in the CLI of the Cisco StarOS operating system for Cisco ASR 5000 Series Aggregation Services Routers could allow an authen
A vulnerability in the CLI of the Cisco StarOS operating system for Cisco ASR 5000 Series Aggregation Services Routers could allow an authenticated, local attacker to overwrite system files that are stored in the flash memory of an affected system. The vulnerability is due to insufficient validation of user-supplied input by the affected operating system. An attacker could exploit this vulnerability by injecting crafted command arguments into a vulnerable CLI command for the affected operating system. A successful exploit could allow the attacker to overwrite or modify arbitrary files that are stored in the flash memory of an affected system. To exploit this vulnerability, the attacker would need to authenticate to an affected system by using valid administrator credentials. Cisco Bug IDs: CSCvf93335.
- Published
- Feb 8, 2018
- Updated
- Jun 16, 2026
- EPSS
- 0.4% · 29th percentile
- CWE
- CWE-20
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Report tools
Action score
17
Monitor
Low priority for now.
- CVSS
- 17 / 40 · 4.4 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.4%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| cisco | staros | cpe:2.3:o:cisco:staros |
| cisco | asr 5000 | cpe:2.3:h:cisco:asr_5000 |
| cisco | asr 5500 | cpe:2.3:h:cisco:asr_5500 |
| cisco | asr 5700 | cpe:2.3:h:cisco:asr_5700 |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cisco staros21.3.0.67664
Versions reported by the vendor
Affected version ranges reported by the assigning authority (cisco). Independent of NVD's CPE analysis and usually ahead of it.
n/a Cisco StarOS for Cisco ASR 5000 Series Aggregation Services Routers
- Cisco StarOS for Cisco ASR 5000 Series Aggregation Services Routersaffected
Same product
cisco: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-20046A vulnerability in the key-based SSH authentication feature of Cisco StarOS Software could allow an authenticated, remote attacker to elevat35Monitor
- CVE-2021-1539Cisco ASR 5000 Series Software Authorization Bypass Vulnerabilities35Monitor
- CVE-2018-0369A vulnerability in the reassembly logic for fragmented IPv4 packets of Cisco StarOS running on virtual platforms could allow an unauthentica35Monitor
- CVE-2021-1353Cisco StarOS IPv4 Denial of Service Vulnerability34Monitor
- CVE-2020-3500Cisco StarOS IPv6 Denial of Service Vulnerability34Monitor
- CVE-2017-6707A vulnerability in the CLI command-parsing code of the Cisco StarOS operating system for Cisco ASR 5000 Series 11.0 through 21.0, 5500 Serie32Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- Administrator privileges are required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- high · data or configuration can be modified
- Availability
- none
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- High
- Availability impact
- None
Weakness class (CWE)
CWE-20 · Improper Input ValidationCVSS vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Buffer Overflow via Environment VariablesCAPEC-10likelihood: High · High
- Server Side Include (SSI) InjectionCAPEC-101likelihood: High · High
- Cross Zone ScriptingCAPEC-104likelihood: Medium · High
- Command Line Execution through SQL InjectionCAPEC-108likelihood: Low · Very High
- Object Relational Mapping InjectionCAPEC-109likelihood: Low · High
- SQL Injection through SOAP Parameter TamperingCAPEC-110likelihood: High · Very High
- Double EncodingCAPEC-120likelihood: Low · Medium
- Subverting Environment Variable ValuesCAPEC-13likelihood: High · Very High
ATT&CK techniques
- Obfuscated Files or InformationT1027
- Masquerading: Invalid Code SignatureT1036.001
- Steal Web Session CookieT1539
- Subvert Trust Controls: Code SigningT1553.002
- Impair Defenses:Impair Command History LoggingT1562.003
- Hijack Execution Flow:Dynamic Linker HijackingT1574.006
- Hijack Execution Flow:Path Interception by PATH Environment VariableT1574.007
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- www.securityfocus.com/bid/103028
- www.securitytracker.com/id/1040340
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180207-asr
Vendor advisories and official records. Exploit/PoC links are deliberately left out.