CVE-2018-0156
A vulnerability in the Smart Install feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote…
- 7.5HighCVSS base score
- 9.4%Exploitation in 30 daysEPSS · top 4.6% of all CVEs
- YesKnown exploitedin CISA's KEV since 3 Mar 2022
- YesPublic exploitsa reference or SSVC says so
Description
A vulnerability in the Smart Install feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of packet data. An attacker could exploit this vulnerability by sending a crafted packet to an affected device on TCP port 4786. Only Smart Install client switches are affected. Cisco devices that are configured as a Smart Install director are not affected by this vulnerability. Cisco Bug IDs: CSCvd40673.
Exploited in the wild
CISA lists this vulnerability in its Known Exploited Vulnerabilities catalog as Cisco IOS Software and Cisco IOS XE Software Smart Install Denial-of-Service Vulnerability.
- Added
- 3 Mar 2022
- Fix due (US federal)
- 17 Mar 2022
- Used by ransomware
- Not known
Apply updates per vendor instructions.
ENISA's EU Vulnerability Database lists it as exploited, from CISA's KEV, since 3 Mar 2022.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: it is being exploited.
Timeline
ID reserved
By cisco
- 4 months later
· 4 months later
Published
- 4 years later
· 4 years later
Added to CISA KEV
Known exploited in the wild
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Analyzed | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 9.4% · top 4.6% of all CVEs (10 Nov 2026)
- CISA SSVC
- Exploitation: active · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
Cisco IOS and IOS XE
- affected Cisco IOS and IOS XE
References
6
- https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04 (opens in a new tab)x_refsource_MISCx_transferred
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-smi (opens in a new tab)x_refsource_CONFIRMx_transferred
- 1040596 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
- 103569 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05 (opens in a new tab)x_refsource_MISCx_transferred
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0156 (opens in a new tab)government-resource
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- CISA KEV catalog (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2018-0979 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2018-0156)Record last updated .