CVE-2026-101090

CRITICALPre-NVD 9.89.8
EchelonGraph scoreMEDIUM confidence

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

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-09-27. A secondary CVSS source baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Trending — 3 sources updated this weekElevated

Also known asEUVD-2026-88025 (ENISA EUVD) · GHSA-62gj-x2f3-j2wj (GitHub Security Advisories)Source: ENISA EUVD

9.8EG
EchelonGraph verdictPlan mitigationNo fix is confirmed yet: 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 on your normal schedule 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: 0.4%CVSS: 9.8Exploit: 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 nezhahq nezha versions 2.2.3 up to and including 2.2.3 as affected. No release containing a fix is confirmed on record.

Nezha 2.2.3 contains a Host header injection regression in the OAuth2 redirect endpoint. When the new optional dashboard_host setting is empty, /api/v1/oauth2/{provider} (cmd/dashboard/controller/oauth2.go) reflects the attacker-supplied HTTP Host header into the redirect_uri sent to the identity provider instead of falling back to the configured install_host. An attacker who induces a victim to begin OAuth2 login via a request that reaches Nezha with a forged Host header can cause an attacker-controlled callback URL to be used as the redirect_uri; if the OAuth2 provider accepts it, the victim's authorization code is delivered to the attacker origin, allowing the attacker to complete the OAuth2 login/binding flow and take over the account. This regresses the fix for GHSA-9rc6-8cjv-rcvx and is configuration-dependent (dashboard_host empty). At the time of the advisory no patched version was available.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
75
EG Risk 75/100

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)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
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. 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 on your normal schedule at low or medium mission impact and sooner than that at high.
EPSS PROB
0.4%
EPSS %ILE
38th
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 (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). 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, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 3 days if the affected system is publicly exposed; 60 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: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.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, Track* at medium and Attend at high mission impact.

No fix is confirmed yet. 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 on your normal schedule at low or medium mission impact and sooner than that at high.

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.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: it starts when an agency identifies the flaw on an asset and updates the CDM Agency and Federal Dashboard, and the directive counts patching, decommissioning the system or another action as remediation. Until a fixed release is applied, mitigate as this page's verdict says.

The score's inputs: 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

September 27, 2026

Last Modified

September 28, 2026

Advisory Details (2)

Auto-updated Oct 31, 2026
🔬 Proof of concept available. No fix on record yet. Sources: github.
GitHub advisoryMentions a patch (unverified)🟡 PoC Available

OAuth2 redirect_uri Host header injection regression when dashboard_host is empty · Advisory · nezhahq/nezha · GitHub

https://github.com/nezhahq/nezha/security/advisories/GHSA-rf68-8gjr-36q7
Web page

Nezha through 2.2.3 Host Header Injection via OAuth2 redirect_uri | Advisories | VulnCheck

https://www.vulncheck.com/advisories/nezha-through-2.2.3-host-header-injection-via-oauth2-redirect-uri

Vendor Advisories for CVE-2026-101090(1)

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

Affected Packages

(1 across 1 ecosystem)
Go(1)
PackageVulnerable rangeFix by version rangeDependents
github.com/nezhahq/nezha2.2.3
  • every version on: no fix on record
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 22× in last 7d / 131× 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 182 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 82 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-02 09:06 UTCEG score recompute
  2. 2026-11-02 09:06 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  3. 2026-11-01 16:33 UTCEPSS rescoreEPSS 0.4% · 38th percentile
  4. 2026-11-01 11:11 UTCEG score recompute
  5. 2026-11-01 11:11 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  6. 2026-10-31 16:31 UTCEPSS rescoreEPSS 0.4% · 38th percentile
  7. 2026-10-31 13:16 UTCEG score recompute
  8. 2026-10-31 13:16 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  9. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.4% · 38th percentile
  10. 2026-10-30 15:19 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  11. 2026-10-29 17:24 UTCEG score recompute
  12. 2026-10-29 17:24 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  13. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.4% · 38th percentile
  14. 2026-10-28 19:29 UTCEG score recompute
  15. 2026-10-28 19:28 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  16. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.4% · 38th percentile
  17. 2026-10-27 21:32 UTCEG score recompute
  18. 2026-10-27 21:32 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  19. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.4% · 38th percentile
  20. 2026-10-27 10:35 UTCEG score recompute
  21. 2026-10-27 10:35 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  22. 2026-10-26 16:30 UTCEPSS rescoreEPSS 0.4% · 38th percentile
  23. 2026-10-26 12:40 UTCEG score recompute
  24. 2026-10-26 12:39 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  25. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.4% · 38th percentile
Show 75 more
  1. 2026-10-25 14:39 UTCEG score recompute
  2. 2026-10-25 14:39 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  3. 2026-10-24 16:44 UTCEG score recompute
  4. 2026-10-24 16:44 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  5. 2026-10-24 16:31 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  6. 2026-10-23 18:49 UTCEG score recompute
  7. 2026-10-23 18:49 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  8. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  9. 2026-10-22 20:53 UTCEG score recompute
  10. 2026-10-22 20:53 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  11. 2026-10-22 16:33 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  12. 2026-10-21 22:48 UTCEG score recompute
  13. 2026-10-21 22:48 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  14. 2026-10-21 16:31 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  15. 2026-10-21 00:53 UTCEG score recompute
  16. 2026-10-21 00:53 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  17. 2026-10-20 16:31 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  18. 2026-10-20 02:57 UTCEG score recompute
  19. 2026-10-20 02:56 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  20. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  21. 2026-10-19 03:04 UTCEG score recompute
  22. 2026-10-19 03:04 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  23. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  24. 2026-10-18 05:07 UTCEG score recompute
  25. 2026-10-18 05:07 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  26. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  27. 2026-10-17 06:46 UTCEG score recompute
  28. 2026-10-17 06:46 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  29. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  30. 2026-10-16 08:08 UTCEG score recompute
  31. 2026-10-16 08:08 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  32. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  33. 2026-10-15 07:11 UTCEG score recompute
  34. 2026-10-15 07:10 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  35. 2026-10-14 16:31 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  36. 2026-10-14 03:05 UTCEG score recompute
  37. 2026-10-14 03:05 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  38. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  39. 2026-10-12 23:10 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  40. 2026-10-12 16:41 UTCEG score recompute
  41. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  42. 2026-10-12 00:46 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  43. 2026-10-11 19:57 UTCEG score recompute
  44. 2026-10-11 19:57 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  45. 2026-10-11 18:28 UTCEG score recompute
  46. 2026-10-11 15:39 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  47. 2026-10-11 15:02 UTCEG score recompute
  48. 2026-10-11 13:47 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  49. 2026-10-11 11:21 UTCEG score recompute
  50. 2026-10-11 11:21 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  51. 2026-10-11 06:54 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  52. 2026-10-11 02:36 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  53. 2026-10-10 21:50 UTCEG score recompute
  54. 2026-10-10 21:50 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  55. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  56. 2026-10-10 17:10 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  57. 2026-10-10 12:51 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  58. 2026-10-10 08:28 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  59. 2026-10-10 04:11 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  60. 2026-10-09 23:50 UTCEG score recompute
  61. 2026-10-09 23:50 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  62. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  63. 2026-10-09 19:32 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  64. 2026-10-09 15:14 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  65. 2026-10-09 10:06 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  66. 2026-10-09 05:45 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  67. 2026-10-09 01:27 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  68. 2026-10-08 21:10 UTCEG score recompute
  69. 2026-10-08 21:09 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  70. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.4% · 27th percentile
  71. 2026-10-08 16:52 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  72. 2026-10-08 11:55 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  73. 2026-10-08 07:31 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8
  74. 2026-10-08 03:13 UTCEG score recompute
  75. 2026-10-08 03:13 UTCGHSA enrichmentGHSA-62gj-x2f3-j2wj · GitHub severity CRITICAL · GitHub CVSS 9.8

Frequently asked(5)

What is CVE-2026-101090?
CVE-2026-101090 is a critical-severity vulnerability; its CVE record was published on September 27, 2026. Nezha 2.2.3 contains a Host header injection regression in the OAuth2 redirect endpoint. When the new optional dashboard_host setting is empty, /api/v1/oauth2/{provider} (cmd/dashboard/controller/oauth2.go) reflects the attacker-supplied HTTP Host header into the redirect_uri sent to the identity…
When was CVE-2026-101090 made public?
CVE-2026-101090 was made public on June 20, 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 September 27, 2026. EchelonGraph's copy of the record carries a last-modified date of September 28, 2026; the record at its source may have been updated since.
Is CVE-2026-101090 actively exploited?
CVE-2026-101090 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (38th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-101090?
CVE-2026-101090 has a CVSS base score of 9.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-101090?
No fix for CVE-2026-101090 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 nezhahq nezha versions 2.2.3 up to and including 2.2.3 as affected. No release containing a fix is confirmed on record. The vendor advisories EchelonGraph has for CVE-2026-101090 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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