CVE-2026-78011

HIGHPre-NVD 8.78.7
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

This high-severity CVE scores 8.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5% (46th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source

Also known asEUVD-2026-67336 (ENISA EUVD) · GHSA-3fgq-vc6q-p4hg (GitHub Security Advisories)Source: ENISA EUVD

8.7EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 8.7Exploit: None knownExposed services: Not assessed

Fireware OS 2026.3.1, Fireware OS 2026.2.2, Fireware OS 12.12.2, Fireware OS 12.5.20 (from the CVE record's solution, WatchGuard Technologies, Inc.) — apply it.

An integer underflow vulnerability in the WatchGuard Fireware OS iked process allows a remote unauthenticated attacker to create a Denial of Service (DoS) condition in VPN processing by sending specially crafted network traffic.

CVSS
8.7
EG Score
8.7HIGHmedium confidence
EG Risk
54
EG Risk 54/100

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)
Severity87% × 45%
Impact severity (EG Severity): CVSS 8.7 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.5% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (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: Fireware OS 2026.3.1, Fireware OS 2026.2.2, Fireware OS 12.12.2, Fireware OS 12.5.20 (from the CVE record's solution, WatchGuard Technologies, Inc.). Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.5%
EPSS %ILE
46th
KEV
Not listed

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

The EG score (8.7): severity, escalated by confirmed exploitation. This CVE's 8.7 is its impact severity (EG Severity), not escalated.

EG Severity
8.7 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source
EG Likelihood
0.5% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-09). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.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)Track at low or medium mission impact; Attend at high (mission-essential systems).

Fireware OS 2026.3.1, Fireware OS 2026.2.2, Fireware OS 12.12.2, Fireware OS 12.5.20 (from the CVE record's solution, WatchGuard Technologies, Inc.). Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (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)14 days if the affected system is publicly exposed; 60 days if it is not.

The score's inputs: In CISA KEV no (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

Published

August 27, 2026

Last Modified

September 3, 2026

Advisory Details (1)

Auto-updated Aug 28, 2026
Fix named in the CVE record's solution (WatchGuard Technologies, Inc.).
Web page

CVE-2026-78011 — Fireware OS Integer Underflow in Iked Allows Unauthenticated Denial of Service (DoS)

https://psirt.watchguard.com/CVE-2026-78011

Vendor Advisories for CVE-2026-78011(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 34× 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 its CVE.org record (CNA or CISA ADP). An arrow marks a change the record states ("CVSS → 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). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

Showing the most recent 100 of 223 rows 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 123 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-13 16:57 UTCEPSS rescoreEPSS 0.5% · 46th percentile
  2. 2026-11-12 16:34 UTCEPSS rescoreEPSS 0.5% · 46th percentile
  3. 2026-11-11 16:40 UTCEPSS rescoreEPSS 0.5% · 46th percentile
  4. 2026-11-10 16:45 UTCEPSS rescoreEPSS 0.5% · 46th percentile
  5. 2026-11-10 01:53 UTCEchelonGraph re-scored
  6. 2026-11-10 01:53 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  7. 2026-11-09 16:36 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  8. 2026-11-08 16:40 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  9. 2026-11-07 16:39 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  10. 2026-11-06 16:39 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  11. 2026-11-05 16:38 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  12. 2026-11-04 16:36 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  13. 2026-11-03 16:49 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  14. 2026-11-03 10:43 UTCEchelonGraph re-scored
  15. 2026-11-03 10:43 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  16. 2026-11-02 16:46 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  17. 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  18. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  19. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  20. 2026-10-29 16:34 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  21. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  22. 2026-10-27 18:59 UTCEchelonGraph re-scored
  23. 2026-10-27 18:59 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  24. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  25. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.5% · 45th percentile
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  1. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.5% · 45th percentile
  2. 2026-10-25 14:01 UTCEchelonGraph re-scored
  3. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  4. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  5. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  6. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  7. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  8. 2026-10-20 08:10 UTCEchelonGraph re-scored
  9. 2026-10-20 08:10 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  10. 2026-10-19 16:33 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  11. 2026-10-18 16:33 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  12. 2026-10-18 03:11 UTCEchelonGraph re-scored
  13. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  14. 2026-10-16 16:44 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  15. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  16. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  17. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  18. 2026-10-13 06:52 UTCEchelonGraph re-scored
  19. 2026-10-13 06:52 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  20. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  21. 2026-10-12 15:37 UTCEchelonGraph re-scored
  22. 2026-10-11 19:23 UTCEchelonGraph re-scored
  23. 2026-10-11 16:39 UTCEchelonGraph re-scored
  24. 2026-10-11 13:57 UTCEchelonGraph re-scored
  25. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  26. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.5% · 44th percentile
  27. 2026-10-10 13:12 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  28. 2026-10-10 01:43 UTCEchelonGraph re-scored
  29. 2026-10-10 01:43 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  30. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  31. 2026-10-09 02:52 UTCEchelonGraph re-scored
  32. 2026-10-09 02:52 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  33. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  34. 2026-10-08 01:10 UTCEchelonGraph re-scored
  35. 2026-10-08 01:10 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  36. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  37. 2026-10-07 06:40 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  38. 2026-10-06 19:13 UTCEchelonGraph re-scored
  39. 2026-10-06 19:13 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  40. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  41. 2026-10-06 07:29 UTCEchelonGraph re-scored
  42. 2026-10-06 07:29 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  43. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  44. 2026-10-05 16:51 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  45. 2026-10-05 04:35 UTCEchelonGraph re-scored
  46. 2026-10-05 04:35 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  47. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  48. 2026-10-04 16:36 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  49. 2026-10-04 05:09 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  50. 2026-10-03 17:43 UTCEchelonGraph re-scored
  51. 2026-10-03 17:43 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  52. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  53. 2026-10-03 06:17 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  54. 2026-10-02 18:50 UTCEchelonGraph re-scored
  55. 2026-10-02 18:50 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  56. 2026-10-02 07:17 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  57. 2026-10-01 19:51 UTCEchelonGraph re-scored
  58. 2026-10-01 19:51 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  59. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  60. 2026-10-01 07:19 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  61. 2026-09-30 19:53 UTCEchelonGraph re-scored
  62. 2026-09-30 19:53 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  63. 2026-09-30 04:20 UTCEchelonGraph re-scored
  64. 2026-09-30 04:20 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  65. 2026-09-29 15:24 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  66. 2026-09-29 12:45 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  67. 2026-09-29 01:18 UTCEchelonGraph re-scored
  68. 2026-09-29 01:18 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  69. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  70. 2026-09-28 13:36 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  71. 2026-09-28 02:10 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  72. 2026-09-27 14:41 UTCEchelonGraph re-scored
  73. 2026-09-27 14:40 UTCGHSA enrichmentGHSA-3fgq-vc6q-p4hg · GitHub severity HIGH
  74. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  75. 2026-09-27 03:14 UTCEchelonGraph re-scored

Frequently asked(5)

What is CVE-2026-78011?
CVE-2026-78011 is a high-severity vulnerability; its CVE record was published on August 27, 2026. An integer underflow vulnerability in the WatchGuard Fireware OS iked process allows a remote unauthenticated attacker to create a Denial of Service (DoS) condition in VPN processing by sending specially crafted network traffic.
When was CVE-2026-78011 made public?
CVE-2026-78011 was made public on August 27, 2026: that is the date its CVE record's CNA, WatchGuard Technologies, Inc., gives for when the vulnerability was made public. The CVE record itself was published on August 27, 2026. EchelonGraph's copy of the record carries a last-modified date of September 3, 2026; the record at its source may have been updated since.
Is CVE-2026-78011 actively exploited?
CVE-2026-78011 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (46th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-78011?
CVE-2026-78011 has a CVSS base score of 8.7 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-78011?
The CVE record's solution for CVE-2026-78011, written by its CNA WatchGuard Technologies, Inc., names the fix: "Fireware OS 2026.3.1, Fireware OS 2026.2.2, Fireware OS 12.12.2, Fireware OS 12.5.20". The vendor advisories EchelonGraph has for CVE-2026-78011 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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