CVE-2026-82456

CRITICALPre-NVD 10.010.0
EchelonGraph scoreMEDIUM confidence

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

Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-29. The CNA's CVSS baseline 10.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: the CNA's CVSS, EPSS, GitHub Security Advisory
Trending — 3 sources updated this weekElevated
10.0EG
EchelonGraph verdictPlan mitigationRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 1.7%CVSS: 10.0Exploit: No code on recordExposed services: Not assessed

No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.

The CVE record's CNA (VulnCheck) lists argoproj-labs argocd-mcp versions 0.8.0 up to but not including 0.9.0 as affected. No release containing a fix is confirmed on record.

argocd-mcp 0.8.0 binds its HTTP transport to every network interface and accepts MCP sessions without requiring caller credentials when ARGOCD_API_TOKEN is configured. Attackers who can reach the listener can invoke the full tool surface using the operator's stored token to create applications, request syncs, and modify Argo CD resources.

CVSS v3
10.0
EG Score
10.0CRITICALmedium confidence
EG Risk
76
EG Risk 76/100

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed (value × EchelonGraph’s weight)
Severity100% × 45%
The EG Score, 10.0 of 10.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (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 is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
EPSS PROB
1.7%
EPSS %ILE
77th
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (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; 60 days if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (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 29, 2026

Last Modified

September 24, 2026

Advisory Details (3)

Auto-updated Oct 8, 2026
No fix on record yet. Sources: github.
Web page

argocd-mcp 0.8.0 Authentication Bypass via Unauthenticated HTTP | Advisories | VulnCheck

https://www.vulncheck.com/advisories/argocd-mcp-0.8.0-authentication-bypass-via-unauthenticated-http
Web page

GitHub - argoproj-labs/mcp-for-argocd: An implementation of Model Context Protocol (MCP) server for Argo CD. · GitHub

https://github.com/argoproj-labs/mcp-for-argocd
GitHub advisoryMentions a patch (unverified)

Binding to an Unrestricted IP Address in argocd-mcp · Advisory · argoproj-labs/mcp-for-argocd · GitHub

https://github.com/argoproj-labs/mcp-for-argocd/security/advisories/GHSA-rp45-5x3v-48mr

Vendor Advisories for CVE-2026-82456(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 28× in last 7d / 183× 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 301 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 201 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-14 09:40 UTCEG score recompute
  2. 2026-10-14 09:39 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  3. 2026-10-13 16:35 UTCEPSS rescoreEPSS 1.7% · 77th percentile
  4. 2026-10-13 07:26 UTCEG score recompute
  5. 2026-10-13 07:25 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  6. 2026-10-12 16:35 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  7. 2026-10-12 14:55 UTCEG score recompute
  8. 2026-10-12 05:19 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  9. 2026-10-11 19:19 UTCEG score recompute
  10. 2026-10-11 16:36 UTCEG score recompute
  11. 2026-10-11 13:54 UTCEG score recompute
  12. 2026-10-11 13:49 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  13. 2026-10-10 20:00 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  14. 2026-10-10 14:02 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  15. 2026-10-10 09:36 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  16. 2026-10-10 05:14 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  17. 2026-10-10 00:45 UTCEG score recompute
  18. 2026-10-10 00:45 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  19. 2026-10-09 20:07 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  20. 2026-10-09 07:00 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  21. 2026-10-09 02:34 UTCEG score recompute
  22. 2026-10-09 02:34 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  23. 2026-10-08 17:13 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  24. 2026-10-08 09:32 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  25. 2026-10-08 05:09 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
Show 75 more
  1. 2026-10-08 00:46 UTCEG score recompute
  2. 2026-10-08 00:45 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  3. 2026-10-07 23:48 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  4. 2026-10-07 10:24 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  5. 2026-10-07 05:56 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  6. 2026-10-07 01:33 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  7. 2026-10-06 21:10 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  8. 2026-10-06 16:29 UTCEG score recompute
  9. 2026-10-06 16:29 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  10. 2026-10-06 15:18 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  11. 2026-10-06 11:49 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  12. 2026-10-06 07:27 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  13. 2026-10-06 00:47 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  14. 2026-10-05 17:50 UTCEG score recompute
  15. 2026-10-05 17:50 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  16. 2026-10-05 17:43 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  17. 2026-10-05 13:27 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  18. 2026-10-05 09:00 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  19. 2026-10-05 04:29 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  20. 2026-10-04 23:58 UTCEG score recompute
  21. 2026-10-04 23:58 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  22. 2026-10-04 23:22 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  23. 2026-10-04 19:35 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  24. 2026-10-04 14:36 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  25. 2026-10-04 09:59 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  26. 2026-10-04 05:36 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  27. 2026-10-04 01:13 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  28. 2026-10-03 19:18 UTCEG score recompute
  29. 2026-10-03 19:18 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  30. 2026-10-03 14:26 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  31. 2026-10-03 13:36 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  32. 2026-10-03 04:51 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  33. 2026-10-03 00:28 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  34. 2026-10-02 19:59 UTCEG score recompute
  35. 2026-10-02 19:59 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  36. 2026-10-02 17:57 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  37. 2026-10-02 15:35 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  38. 2026-10-02 11:00 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  39. 2026-10-02 06:14 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  40. 2026-10-02 00:36 UTCEG score recompute
  41. 2026-10-02 00:36 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  42. 2026-10-01 19:50 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  43. 2026-10-01 19:48 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  44. 2026-10-01 14:10 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  45. 2026-10-01 09:47 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  46. 2026-10-01 05:24 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  47. 2026-10-01 00:58 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  48. 2026-09-30 19:48 UTCEG score recompute
  49. 2026-09-30 19:48 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  50. 2026-09-30 15:04 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  51. 2026-09-30 08:11 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  52. 2026-09-30 03:48 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  53. 2026-09-29 15:32 UTCEG score recompute
  54. 2026-09-29 15:32 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  55. 2026-09-29 11:10 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  56. 2026-09-29 05:52 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  57. 2026-09-29 01:29 UTCEG score recompute
  58. 2026-09-29 01:29 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  59. 2026-09-28 21:07 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  60. 2026-09-28 15:46 UTCEG score recompute
  61. 2026-09-28 15:46 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  62. 2026-09-28 13:52 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  63. 2026-09-28 11:10 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  64. 2026-09-28 06:47 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  65. 2026-09-28 02:24 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  66. 2026-09-27 22:01 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  67. 2026-09-27 17:24 UTCEG score recompute
  68. 2026-09-27 17:23 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  69. 2026-09-27 13:48 UTCEPSS rescoreEPSS 1.7% · 76th percentile
  70. 2026-09-27 12:52 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  71. 2026-09-27 08:28 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  72. 2026-09-27 04:05 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  73. 2026-09-26 23:05 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0
  74. 2026-09-26 18:13 UTCEG score recompute
  75. 2026-09-26 18:13 UTCGHSA enrichmentGHSA-p2x5-x87w-v2xj · GitHub severity CRITICAL · GitHub CVSS 10.0

Public detection templates

(1 reference)

A public Nuclei detection template is referenced for this CVE. A detection template checks whether a system is affected; it is not necessarily exploit code.

  • Nucleihttp/cves/2026/CVE-2026-82456.yaml
    Published Sep 18, 2026

    argocd-mcp 0.8.0 - Unauthenticated MCP Session and Tool Access

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-82456?
CVE-2026-82456 is a critical-severity vulnerability; its CVE record was published on August 29, 2026. argocd-mcp 0.8.0 binds its HTTP transport to every network interface and accepts MCP sessions without requiring caller credentials when ARGOCDAPITOKEN is configured. Attackers who can reach the listener can invoke the full tool surface using the operator's stored token to create applications,…
When was CVE-2026-82456 made public?
CVE-2026-82456 was made public on August 25, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on August 29, 2026. EchelonGraph's copy of the record carries a last-modified date of September 24, 2026; the record at its source may have been updated since.
Is CVE-2026-82456 actively exploited?
CVE-2026-82456 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1.7% probability of exploitation in the next 30 days (77th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-82456?
CVE-2026-82456 has a CVSS base score of 10.0 (the CNA's own assessment, by vulncheck; NVD's own analysis pending).
How do I remediate CVE-2026-82456?
No fix for CVE-2026-82456 is confirmed yet. Until one is published, 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 watch the vendor's advisory for the fix. The CVE record's CNA (VulnCheck) lists argoproj-labs argocd-mcp versions 0.8.0 up to but not including 0.9.0 as affected. No release containing a fix is confirmed on record. The vendor advisories EchelonGraph has for CVE-2026-82456 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-82456

Explore →

Is Your Infrastructure Affected by CVE-2026-82456?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs