CVE-2018-0155

CRITICALNVD 8.69.0
EchelonGraph scoreHIGH confidence

“▲” beside the score: it is higher than NVD's CVSS score.

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2022-03-03), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 8.6 retained for reference. The 9.0 is the floor for confirmed exploitation, not an impact rating: this CVE's impact severity (EG Severity) is CVSS 8.6 HIGH under GitHub Security Advisory CVSS. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: CISA Known Exploited Vulnerabilities catalog, EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 3 sources updated this weekExploited in the wild

Also known asEUVD-2018-0978 (ENISA EUVD) · GHSA-qmg7-32mc-92p9 (GitHub Security Advisories)Source: ENISA EUVD

9.0EG
EchelonGraph verdictMitigate nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV) — the reason this is sooner than the SSVC decision on this page at low or medium mission impact
CISA-KEV: ExploitedEPSS PROB: 7.7%CVSS: 8.6Exploit: No code on recordExposed services: Not assessed

No fix has been recorded since the CVE record was published in 2018 — use a compensating control (WAF / firewall / segmentation) and check the vendor's advisory.

A vulnerability in the Bidirectional Forwarding Detection (BFD) offload implementation of Cisco Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches could allow an unauthenticated, remote attacker to cause a crash of the iosd process, causing a denial of service (DoS) condition. The vulnerability is due to insufficient error handling when the BFD header in a BFD packet is incomplete. An attacker could exploit this vulnerability by sending a crafted BFD message to or across an affected switch. A successful exploit could allow the attacker to trigger a reload of the system. This vulnerability affects Catalyst 4500 Supervisor Engine 6-E (K5), Catalyst 4500 Supervisor Engine 6L-E (K10), Catalyst 4500 Supervisor Engine 7-E (K10), Catalyst 4500 Supervisor Engine 7L-E (K10), Catalyst 4500E Supervisor Engine 8-E (K10), Catalyst 4500E Supervisor Engine 8L-E (K10), Catalyst 4500E Supervisor Engine 9-E (K10), Catalyst 4500-X Series Switches (K10), Catalyst 4900M Switch (K5), Catalyst 4948E Ethernet Switch (K5). Cisco Bug IDs: CSCvc40729.

CVSS v3
8.6
EG Score
9.0CRITICALhigh confidence
EG Risk
94
EG Risk 94/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity86% × 45%
Impact severity (EG Severity): CVSS 8.6 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation100% × 40%
Fixed at 100% for a CISA KEV listing: EchelonGraph's rule.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Attend at low or medium mission impact; Act at high (mission-essential systems).
Exploitation active (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: No fix has been recorded since the CVE record was published in 2018. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation sooner than your normal schedule at low or medium mission impact and as soon as possible at high.
EPSS PROB
7.7%
EPSS %ILE
94th
KEV
⚠ Exploited

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is the CISA KEV floor for confirmed exploitation, not an impact rating: its impact severity (EG Severity) is CVSS 8.6 HIGH.

EG Severity
8.6 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
7.7% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
CISA KEV and EG-KEV Tier 1 (exploited in the wild)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Attend at medium mission impactAttend at low or medium mission impact; Act at high (mission-essential systems).CISA BOD 26-04: 3 days if the affected system is publicly exposed; 14 days if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: this CVE is in CISA's KEV catalog, and CISA's required action for it, quoted below, applies whether or not a fix is released.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Attend at low or medium mission impact; Act at high (mission-essential systems).

No fix has been recorded since the CVE record was published in 2018. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation sooner than your normal schedule at low or medium mission impact and as soon as possible at high.

Exploitation active (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)3 days if the affected system is publicly exposed; 14 days if it is not.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: this CVE is in CISA's KEV catalog, and CISA's required action for it, quoted below, applies whether or not a fix is released.

The score's inputs: In CISA KEV yes (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

CISA required action“Apply updates per vendor instructions.”

Quoted verbatim from CISA's Known Exploited Vulnerabilities catalog. CISA directs it at US federal civilian executive branch agencies under Binding Operational Directive (BOD) 26-04, which replaced BOD 22-01 on 10 June 2026; it is not EchelonGraph's advice. CISA's notes: https://nvd.nist.gov/vuln/detail/CVE-2018-0155

Published

March 28, 2018

Last Modified

January 13, 2026

Advisory Details (5)

Auto-updated Oct 26, 2026
⚠️ Actively exploited (CISA KEV, CISA Vulnrichment). No fix on record since 2018. Sources: cisa.
CISA🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0155
Web page

Cisco IOS and IOS XE Software Bidirectional Forwarding Detection Denial of Service Vulnerability

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-bfd
Web page

Rockwell Automation Stratix Industrial Managed Ethernet Switch | CISA

https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05
Web page

PSIRT.COM — Product Security Incident Response Team

http://www.securityfocus.com/bid/103565

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 21× in last 7d / 135× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 1,082 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 982 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 21:17 UTCEG score recompute
  2. 2026-11-01 21:17 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  3. 2026-11-01 16:28 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  4. 2026-10-31 22:48 UTCEG score recompute
  5. 2026-10-31 22:48 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  6. 2026-10-31 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  7. 2026-10-31 00:19 UTCEG score recompute
  8. 2026-10-31 00:19 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  9. 2026-10-30 16:28 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  10. 2026-10-30 01:50 UTCEG score recompute
  11. 2026-10-30 01:50 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  12. 2026-10-29 16:28 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  13. 2026-10-29 03:21 UTCEG score recompute
  14. 2026-10-29 03:21 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  15. 2026-10-28 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  16. 2026-10-28 04:52 UTCEG score recompute
  17. 2026-10-28 04:52 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  18. 2026-10-27 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  19. 2026-10-27 06:22 UTCEG score recompute
  20. 2026-10-27 06:22 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  21. 2026-10-26 16:26 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  22. 2026-10-26 07:52 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  23. 2026-10-25 19:28 UTCEG score recompute
  24. 2026-10-25 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  25. 2026-10-25 09:23 UTCEG score recompute
Show 75 more
  1. 2026-10-25 09:23 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  2. 2026-10-24 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  3. 2026-10-24 10:53 UTCEG score recompute
  4. 2026-10-24 10:53 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  5. 2026-10-23 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  6. 2026-10-23 12:23 UTCEG score recompute
  7. 2026-10-23 12:23 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  8. 2026-10-22 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  9. 2026-10-22 13:53 UTCEG score recompute
  10. 2026-10-22 13:53 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  11. 2026-10-21 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  12. 2026-10-21 15:24 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  13. 2026-10-20 16:54 UTCEG score recompute
  14. 2026-10-20 16:54 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  15. 2026-10-20 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  16. 2026-10-19 18:23 UTCEG score recompute
  17. 2026-10-19 18:23 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  18. 2026-10-19 16:26 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  19. 2026-10-18 19:54 UTCEG score recompute
  20. 2026-10-18 19:54 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  21. 2026-10-18 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  22. 2026-10-18 10:25 UTCEG score recompute
  23. 2026-10-17 21:24 UTCEG score recompute
  24. 2026-10-17 21:24 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  25. 2026-10-17 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  26. 2026-10-16 22:54 UTCEG score recompute
  27. 2026-10-16 22:54 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  28. 2026-10-16 16:29 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  29. 2026-10-16 00:24 UTCEG score recompute
  30. 2026-10-16 00:24 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  31. 2026-10-15 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  32. 2026-10-15 01:53 UTCEG score recompute
  33. 2026-10-15 01:53 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  34. 2026-10-14 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  35. 2026-10-14 03:21 UTCEG score recompute
  36. 2026-10-14 03:20 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  37. 2026-10-13 16:27 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  38. 2026-10-13 04:49 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  39. 2026-10-12 20:23 UTCEG score recompute
  40. 2026-10-12 16:28 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  41. 2026-10-12 06:18 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  42. 2026-10-12 01:54 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  43. 2026-10-11 21:32 UTCEG score recompute
  44. 2026-10-11 21:32 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  45. 2026-10-11 17:11 UTCEG score recompute
  46. 2026-10-11 17:11 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  47. 2026-10-11 13:41 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  48. 2026-10-11 12:49 UTCEG score recompute
  49. 2026-10-11 12:49 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  50. 2026-10-11 08:27 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  51. 2026-10-11 04:05 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  52. 2026-10-10 23:43 UTCEG score recompute
  53. 2026-10-10 23:43 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  54. 2026-10-10 19:55 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  55. 2026-10-10 19:22 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  56. 2026-10-10 15:00 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  57. 2026-10-10 10:38 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  58. 2026-10-10 06:14 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  59. 2026-10-10 01:53 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  60. 2026-10-09 21:31 UTCEG score recompute
  61. 2026-10-09 21:31 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  62. 2026-10-09 20:02 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  63. 2026-10-09 17:10 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  64. 2026-10-09 12:47 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  65. 2026-10-09 08:26 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  66. 2026-10-09 04:05 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  67. 2026-10-08 23:43 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  68. 2026-10-08 19:22 UTCEG score recompute
  69. 2026-10-08 19:22 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  70. 2026-10-08 16:36 UTCEPSS rescoreEPSS 7.7% · 94th percentile
  71. 2026-10-08 15:00 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  72. 2026-10-08 10:38 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  73. 2026-10-08 06:14 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6
  74. 2026-10-08 01:52 UTCEG score recompute
  75. 2026-10-08 01:52 UTCGHSA enrichmentGHSA-qmg7-32mc-92p9 · GitHub severity HIGH · GitHub CVSS 8.6

Frequently asked(6)

What is CVE-2018-0155?
CVE-2018-0155 is a critical-severity vulnerability; its CVE record was published on March 28, 2018. A vulnerability in the Bidirectional Forwarding Detection (BFD) offload implementation of Cisco Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches could allow an unauthenticated, remote attacker to cause a crash of the iosd process, causing a denial of service (DoS) condition.…
When was CVE-2018-0155 made public?
CVE-2018-0155 was made public on March 28, 2018: that is the date its CVE record's CNA, Cisco Systems, Inc., gives for when the vulnerability was made public. The CVE record itself was published on March 28, 2018. EchelonGraph's copy of the record carries a last-modified date of January 13, 2026; the record at its source may have been updated since.
Is CVE-2018-0155 actively exploited?
Yes. CISA added CVE-2018-0155 to the Known Exploited Vulnerabilities catalog on March 3, 2022, affecting Cisco Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate attention. No fix has been recorded since the CVE record was published in 2018. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation.
What is the CVSS score of CVE-2018-0155?
CVE-2018-0155 has a CVSS v3 base score of 8.6 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0 (CRITICAL).
Which products are affected by CVE-2018-0155?
CVE-2018-0155 affects Cisco Catalyst 4500 Series Switches and Cisco Catalyst 4500-X Series Switches.
How do I remediate CVE-2018-0155?
No fix for CVE-2018-0155 has been recorded since its CVE record was published in 2018. Restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and check the vendor's advisory for a fix.

Dependency Blast Radius

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