CVE-2026-45363

CRITICALPre-NVD 9.19.1
EchelonGraph scoreMEDIUM confidence

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

This critical-severity CVE scores 9.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4% (30th percentile of EPSS-scored CVEs). GitHub Security Advisory CVSS 7.4 is lower than this score; a lower GitHub score revises it only when its advisory is newer than the CVE record's last change, and this advisory (published 2026-05-18) is not newer than that change (2026-10-24), so it does not.

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

Also known asEUVD-2026-44516 (ENISA EUVD) · GHSA-c32j-vqhx-rx3x (GitHub Security Advisories)Source: ENISA EUVD

9.1EG
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: 0.4%CVSS: 9.1Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

ruby-jwt is a Ruby implementation of the RFC 7519 OAuth JSON Web Token standard. Prior to 2.10.3 and 3.2.0, JWT.decode(token, '', true, algorithm: 'HS256') accepts an attacker-forged token because OpenSSL::HMAC.digest('SHA256', '', payload) returns a valid digest under an empty key and no empty-key precondition exists in the HMAC algorithm. The same path is reached when a keyfinder block or key_finder: argument returns an empty string, nil, or an array containing nil for an unknown key, affecting HS256, HS384, and HS512 verification through JWT.decode and JWT::EncodedToken#verify_signature!. This issue is fixed in versions 2.10.3 and 3.2.0.

CVSS v3
9.1
EG Score
9.1CRITICALmedium confidence
EG Risk
56
EG Risk 56/100

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)
Severity91% × 45%
Impact severity (EG Severity): CVSS 9.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.4% × 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 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: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.4%
EPSS %ILE
30th
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 (9.1): severity, escalated by confirmed exploitation. This CVE's 9.1 is its impact severity (EG Severity), not escalated.

EG Severity
9.1 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-12). 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: 3 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).

A fix is available. 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 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.

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

May 18, 2026

Last Modified

October 24, 2026

Advisory Details (5)

Auto-updated Sep 16, 2026
Patch available. Sources: github, github_commit, github_release.
GitHub advisoryMentions a patch (unverified)

Empty-key HMAC bypass; cross-language sibling of CVE-2026-44351 · Advisory · jwt/ruby-jwt · GitHub

https://github.com/jwt/ruby-jwt/security/advisories/GHSA-c32j-vqhx-rx3x
GitHub release Patch Available

jwt-3.2.0

Patch available: jwt/ruby-jwt v3.2.0

https://github.com/jwt/ruby-jwt/releases/tag/v3.2.0
GitHub release Patch Available

jwt-2.10.3

Patch available: jwt/ruby-jwt v2.10.3

https://github.com/jwt/ruby-jwt/releases/tag/v2.10.3
GitHub commit Patch Available

commit db560b769a07 (jwt/ruby-jwt)

Patch available: jwt/ruby-jwt v3.2.0 (contains commit db560b769a07)

https://github.com/jwt/ruby-jwt/commit/db560b769a07bd9724e77ff505011ac01872106f
GitHub commit Patch Available

commit 9820020869ad (jwt/ruby-jwt)

Patch available: jwt/ruby-jwt v2.10.3 (contains commit 9820020869ad)

https://github.com/jwt/ruby-jwt/commit/9820020869ad147b941e49d96ab8beba35532964

Patch Availability(3)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatrubygem-jwt-0:2.10.3-1.el9sat2026-09-03redhat
rubygemsjwt @ 3.2.0 (fixes >= 3.0.0, < 3.2.0)—ghsa
rubygemsjwt @ 2.10.3 (fixes < 2.10.3)—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
ruby-jwt2.2.2-1 ... 3.2.0-1 (8 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
ruby-jwt2.5.0-1
  • every version up to 2.5.0-1+deb12u1: fixed in 2.5.0-1+deb12u1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
ruby-jwt2.7.1-1
  • every version up to 2.7.1-1+deb13u1: fixed in 2.7.1-1+deb13u1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
ruby-jwt2.7.1-1, 3.1.2-1
  • every version up to 3.2.0-1: fixed in 3.2.0-1
—
RubyGems(1)
PackageVulnerable rangeFix by version rangeDependents
jwt0.1.1 ... 2.9.3 (49 versions)
  • 3.0.0 up to 3.2.0: fixed in 3.2.0
  • every version up to 2.10.3: fixed in 2.10.3
—

Weakness Classification(3)

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

Data Freshness Timeline

(refreshed 19× in last 7d / 72× 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 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). "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 217 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 117 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-13 16:52 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  2. 2026-11-12 22:42 UTCEchelonGraph re-scored
  3. 2026-11-12 22:42 UTCVendor advisory
  4. 2026-11-12 22:42 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  5. 2026-11-12 16:34 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  6. 2026-11-11 21:18 UTCEchelonGraph re-scored
  7. 2026-11-11 21:18 UTCVendor advisory
  8. 2026-11-11 21:18 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  9. 2026-11-11 16:39 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  10. 2026-11-10 20:13 UTCEchelonGraph re-scored
  11. 2026-11-10 20:13 UTCVendor advisory
  12. 2026-11-10 20:13 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  13. 2026-11-10 16:44 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  14. 2026-11-09 19:07 UTCEchelonGraph re-scored
  15. 2026-11-09 19:07 UTCVendor advisory
  16. 2026-11-09 19:07 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  17. 2026-11-09 16:35 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  18. 2026-11-08 17:59 UTCEchelonGraph re-scored
  19. 2026-11-08 17:59 UTCVendor advisory
  20. 2026-11-08 17:59 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  21. 2026-11-08 16:39 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  22. 2026-11-07 16:54 UTCEchelonGraph re-scored
  23. 2026-11-07 16:54 UTCVendor advisory
  24. 2026-11-07 16:54 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  25. 2026-11-07 16:39 UTCEPSS rescoreEPSS 0.4% · 30th percentile
Show 75 more
  1. 2026-11-06 16:38 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  2. 2026-11-06 15:49 UTCEchelonGraph re-scored
  3. 2026-11-06 15:49 UTCVendor advisory
  4. 2026-11-06 15:49 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  5. 2026-11-06 09:25 UTCOSV refresh
  6. 2026-11-05 16:37 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  7. 2026-11-05 14:44 UTCEchelonGraph re-scored
  8. 2026-11-05 14:44 UTCVendor advisory
  9. 2026-11-05 14:44 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  10. 2026-11-04 16:35 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  11. 2026-11-04 13:39 UTCEchelonGraph re-scored
  12. 2026-11-04 13:39 UTCVendor advisory
  13. 2026-11-04 13:39 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  14. 2026-11-03 16:48 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  15. 2026-11-03 12:34 UTCEchelonGraph re-scored
  16. 2026-11-03 12:34 UTCVendor advisory
  17. 2026-11-03 12:34 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  18. 2026-11-02 16:45 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  19. 2026-11-02 11:29 UTCEchelonGraph re-scored
  20. 2026-11-02 11:29 UTCVendor advisory
  21. 2026-11-02 11:29 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  22. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  23. 2026-11-01 10:23 UTCVendor advisory
  24. 2026-11-01 10:23 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  25. 2026-11-01 07:48 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
  26. 2026-11-01 07:48 UTCEchelonGraph re-scored
  27. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  28. 2026-10-31 09:18 UTCEchelonGraph re-scored
  29. 2026-10-31 09:18 UTCVendor advisory
  30. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  31. 2026-10-30 08:12 UTCEchelonGraph re-scored
  32. 2026-10-30 08:12 UTCVendor advisory
  33. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  34. 2026-10-29 07:07 UTCEchelonGraph re-scored
  35. 2026-10-29 07:07 UTCVendor advisory
  36. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  37. 2026-10-28 06:02 UTCEchelonGraph re-scored
  38. 2026-10-28 06:02 UTCVendor advisory
  39. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  40. 2026-10-27 04:57 UTCEchelonGraph re-scored
  41. 2026-10-27 04:57 UTCVendor advisory
  42. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  43. 2026-10-25 23:44 UTCEchelonGraph re-scored
  44. 2026-10-25 23:44 UTCVendor advisory
  45. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  46. 2026-10-25 14:26 UTCEchelonGraph re-scored
  47. 2026-10-24 22:26 UTCEchelonGraph re-scored
  48. 2026-10-24 22:26 UTCVendor advisory
  49. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  50. 2026-10-24 02:48 UTCEchelonGraph re-scored
  51. 2026-10-24 02:48 UTCVendor advisory
  52. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  53. 2026-10-23 01:43 UTCEchelonGraph re-scored
  54. 2026-10-23 01:43 UTCVendor advisory
  55. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  56. 2026-10-22 00:37 UTCEchelonGraph re-scored
  57. 2026-10-22 00:37 UTCVendor advisory
  58. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  59. 2026-10-20 23:29 UTCEchelonGraph re-scored
  60. 2026-10-20 23:29 UTCVendor advisory
  61. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  62. 2026-10-19 22:24 UTCEchelonGraph re-scored
  63. 2026-10-19 22:24 UTCVendor advisory
  64. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  65. 2026-10-18 21:17 UTCEchelonGraph re-scored
  66. 2026-10-18 21:17 UTCVendor advisory
  67. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  68. 2026-10-18 03:38 UTCEchelonGraph re-scored
  69. 2026-10-17 20:12 UTCEchelonGraph re-scored
  70. 2026-10-17 20:12 UTCVendor advisory
  71. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  72. 2026-10-16 19:05 UTCEchelonGraph re-scored
  73. 2026-10-16 19:05 UTCVendor advisory
  74. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.4% · 28th percentile
  75. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.4% · 28th percentile

Frequently asked(5)

What is CVE-2026-45363?
CVE-2026-45363 is a critical-severity vulnerability; its CVE record was published on May 18, 2026. ruby-jwt is a Ruby implementation of the RFC 7519 OAuth JSON Web Token standard. Prior to 2.10.3 and 3.2.0, JWT.decode(token, '', true, algorithm: 'HS256') accepts an attacker-forged token because OpenSSL::HMAC.digest('SHA256', '', payload) returns a valid digest under an empty key and no empty-key…
When was the CVE record for CVE-2026-45363 published?
The CVE record for CVE-2026-45363 was published on May 18, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 24, 2026; the record at its source may have been updated since.
Is CVE-2026-45363 actively exploited?
CVE-2026-45363 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (30th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-45363?
CVE-2026-45363 has a CVSS base score of 9.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-45363?
A fix for CVE-2026-45363 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-45363 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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