Cisco NX-OS Software Cisco Fabric Services Denial of Service Vulnerability
A vulnerability in the Cisco Fabric Services component of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a buffer overflow, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient validation of Cisco Fabric Services packets. An attacker could exploit this vulnerability by sending a crafted Cisco Fabric Services packet to an affected device. A successful exploit could allow the attacker to cause a buffer overflow, resulting in process crashes and a DoS condition on the device. MDS 9000 Series Multilayer Switches are affected running software versions prior to 6.2(25), 8.1(1b), 8.3(1). Nexus 3000 Series Switches are affected running software versions prior to 7.0(3)I4(9) and 7.0(3)I7(4). Nexus 3500 Platform Switches are affected running software versions prior to 6.0(2)A8(10) and 7.0(3)I7(4). Nexus 3600 Platform Switches are affected running software versions prior to 7.0(3)F3(5) Nexus 7000 and 7700 Series Switches are affected running software versions prior to 6.2(22) and 8.2(3). Nexus 9000 Series Switches in Standalone NX-OS Mode are affected running software versions prior to 7.0(3)I4(9) and 7.0(3)I7(4). Nexus 9500 R-Series Line Cards and Fabric Modules are affected running software versions prior to 7.0(3)F3(5). UCS 6200, 6300, and 6400 Fabric Interconnects are affected running software versions prior to 3.2(3j) and 4.0(2a).
- Published
- Mar 11, 2019
- Updated
- Jun 16, 2026
- EPSS
- 2.4% · 84th percentile
- CWE
- CWE-20
Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.
Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 2.4%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 7.5
- CNA · cisco
- 8.6
- 1.1 point gap
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| cisco | nx-os | cpe:2.3:o:cisco:nx-os |
| cisco | mds 9000 | cpe:2.3:h:cisco:mds_9000 |
| cisco | nexus 3500 | cpe:2.3:h:cisco:nexus_3500 |
| cisco | nexus 3000 | cpe:2.3:h:cisco:nexus_3000 |
| cisco | nexus 3600 | cpe:2.3:h:cisco:nexus_3600 |
| cisco | nexus 7000 | cpe:2.3:h:cisco:nexus_7000 |
| cisco | nexus 7700 | cpe:2.3:h:cisco:nexus_7700 |
| cisco | nexus 9000 | cpe:2.3:h:cisco:nexus_9000 |
| cisco | nexus 9500 | cpe:2.3:h:cisco:nexus_9500 |
| cisco | ucs 6200 | cpe:2.3:h:cisco:ucs_6200 |
| cisco | ucs 6300 | cpe:2.3:h:cisco:ucs_6300 |
| cisco | ucs 6400 | cpe:2.3:h:cisco:ucs_6400 |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cisco nx-os8.2 and later · before 8.3\(1\)
- cisco nx-os7.0\(3\) and later · before 7.0\(3\)i7\(4\)
- cisco nx-os7.0\(3\)i5 and later · before 7.0\(3\)i7\(4\)
- cisco nx-os7.0\(3\)f3 and later · before 7.0\(3\)f3\(3c\)
- cisco nx-os7.2 and later · before 8.2\(3\)
- cisco nx-os7.0\(3\)f1 and later · before 7.0\(3\)f3\(3c\)
- cisco nx-os7.3 and later · before 8.1\(1b\)
- cisco nx-os5.2 and later · before 6.2\(25\)
- cisco nx-os7.0\(3\)i4 and later · before 7.0\(3\)i4\(9\)
- cisco nx-os6.2 and later · before 6.2\(22\)
- cisco nx-osbefore 6.2\(22\)
- cisco nx-osbefore 7.0\(3\)i4\(9\)
- cisco nx-os6.0\(2\)a8 and later · before 6.0\(2\)a8\(10\)
- cisco nx-osup to 6.0\(2\)a8 inclusive
- cisco nx-osup to 7.0\(3\)i4 inclusive
- cisco nx-os4.0 and later · before 4.0\(2a\)
- cisco nx-osbefore 3.2\(3j\)
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.
Cisco MDS 9000 Series Multilayer Switches
- unspecified and later · before 6.2(25)affected
- unspecified and later · before 8.1(1b)affected
- unspecified and later · before 8.3(1)affected
Cisco Nexus 3000 Series Switches
- unspecified and later · before 7.0(3)I4(9)affected
- unspecified and later · before 7.0(3)I7(4)affected
Cisco Nexus 3500 Platform Switches
- unspecified and later · before 6.0(2)A8(10)affected
- unspecified and later · before 7.0(3)I7(4)affected
Cisco Nexus 3600 Platform Switches
- unspecified and later · before 7.0(3)F3(5)affected
Cisco Nexus 7000 and 7700 Series Switches
- unspecified and later · before 6.2(22)affected
- unspecified and later · before 8.2(3)affected
Cisco Nexus 9000 Series Switches in Standalone NX-OS Mode
- unspecified and later · before 7.0(3)I4(9)affected
- unspecified and later · before 7.0(3)I7(4)affected
Cisco Nexus 9500 R-Series Line Cards and Fabric Modules
- unspecified and later · before 7.0(3)F3(5)affected
Cisco UCS 6200, 6300, and 6400 Fabric Interconnects
- unspecified and later · before 3.2(3j)affected
- unspecified and later · before 4.0(2a)affected
Same product
cisco: all recordsOther highest-scoring records for the same primary product.
- CVE-2024-20399Cisco NX-OS Software CLI Command Injection VulnerabilityKEV57Plan
- CVE-2018-0301A vulnerability in the NX-API feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to craft a packet to the manag44Plan
- CVE-2016-1453Buffer overflow in the Overlay Transport Virtualization (OTV) GRE feature in Cisco NX-OS 5.0 through 7.3 on Nexus 7000 and 7700 devices allo41Plan
- CVE-2018-0310A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remot40Plan
- CVE-2022-20650Cisco NX-OS Software NX-API Command Injection Vulnerability39Monitor
- CVE-2016-1341Cisco NX-OS 7.0(1)N1(1), 7.0(1)N1(3), and 7.0(4)N1(1) on Nexus 2000 Fabric Extender devices has a blank root password, which allows local us39Monitor
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
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-20 · Improper Input ValidationCVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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/107395
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190306-nxos-fabric-dos
Vendor advisories and official records. Exploit/PoC links are deliberately left out.