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.
CVE-2026-45363
“—” 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.
Also known asEUVD-2026-44516 (ENISA EUVD) · GHSA-c32j-vqhx-rx3x (GitHub Security Advisories)Source: ENISA EUVD
- High severity, but no confirmed exploitation yet
A fix is available — apply it.
- CVSS v3
- 9.1
- EG Score
- 9.1CRITICALmedium confidence
- EG Risk
- 56EG 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 2026-10-31). 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, 2026Empty-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-rx3xjwt-3.2.0
Patch available: jwt/ruby-jwt v3.2.0
https://github.com/jwt/ruby-jwt/releases/tag/v3.2.0jwt-2.10.3
Patch available: jwt/ruby-jwt v2.10.3
https://github.com/jwt/ruby-jwt/releases/tag/v2.10.3commit db560b769a07 (jwt/ruby-jwt)
Patch available: jwt/ruby-jwt v3.2.0 (contains commit db560b769a07)
https://github.com/jwt/ruby-jwt/commit/db560b769a07bd9724e77ff505011ac01872106fcommit 9820020869ad (jwt/ruby-jwt)
Patch available: jwt/ruby-jwt v2.10.3 (contains commit 9820020869ad)
https://github.com/jwt/ruby-jwt/commit/9820020869ad147b941e49d96ab8beba35532964Vendor Advisories for CVE-2026-45363(5)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
- RHSA-2026:63327Red Hat Product SecurityHigh
Red Hat Security Advisory: Satellite 6.16.13 Async Update
- RHSA-2026:63385Red Hat Product SecurityHigh
Red Hat Security Advisory: Satellite 6.19.4 Async Update
- RHSA-2026:63387Red Hat Product SecurityHigh
Red Hat Security Advisory: Satellite 6.17.11 Async Update
- RHSA-2026:63386Red Hat Product SecurityHigh
Red Hat Security Advisory: Satellite 6.18.9 Async Update
- GHSA-c32j-vqhx-rx3xGitHub Security AdvisoriesHigh
ruby-jwt: Empty-key HMAC bypass; cross-language sibling of CVE-2026-44351
Patch Availability(3)
| Vendor / Ecosystem | Fix (by version range) / Patch | Released | Source |
|---|---|---|---|
| redhat | rubygem-jwt-0:2.10.3-1.el9sat | 2026-09-03 | redhat |
| rubygems | jwt @ 3.2.0 (fixes >= 3.0.0, < 3.2.0) | — | ghsa |
| rubygems | jwt @ 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)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| ruby-jwt | 2.2.2-1 ... 3.2.0-1 (8 versions) |
| — |
Debian:12(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| ruby-jwt | 2.5.0-1 |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| ruby-jwt | 2.7.1-1 |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| ruby-jwt | 2.7.1-1, 3.1.2-1 |
| — |
RubyGems(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| jwt | 0.1.1 ... 2.9.3 (49 versions) |
| — |
Weakness Classification(3)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 21× in last 7d / 78× 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 171 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 71 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.4% · 30th percentile
- 2026-11-01 10:23 UTCVendor advisory
- 2026-11-01 10:23 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
- 2026-11-01 07:48 UTCGHSA enrichmentGHSA-c32j-vqhx-rx3x · GitHub severity HIGH · GitHub CVSS 7.4
- 2026-11-01 07:48 UTCEG score recompute
- 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.4% · 30th percentile
- 2026-10-31 09:18 UTCEG score recompute
- 2026-10-31 09:18 UTCVendor advisory
- 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.4% · 30th percentile
- 2026-10-30 08:12 UTCEG score recompute
- 2026-10-30 08:12 UTCVendor advisory
- 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.4% · 30th percentile
- 2026-10-29 07:07 UTCEG score recompute
- 2026-10-29 07:07 UTCVendor advisory
- 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.4% · 30th percentile
- 2026-10-28 06:02 UTCEG score recompute
- 2026-10-28 06:02 UTCVendor advisory
- 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.4% · 30th percentile
- 2026-10-27 04:57 UTCEG score recompute
- 2026-10-27 04:57 UTCVendor advisory
- 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.4% · 30th percentile
- 2026-10-25 23:44 UTCEG score recompute
- 2026-10-25 23:44 UTCVendor advisory
- 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.4% · 30th percentile
- 2026-10-25 14:26 UTCEG score recompute
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- 2026-10-24 22:26 UTCEG score recompute
- 2026-10-24 22:26 UTCVendor advisory
- 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.4% · 29th percentile
- 2026-10-24 02:48 UTCEG score recompute
- 2026-10-24 02:48 UTCVendor advisory
- 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.4% · 29th percentile
- 2026-10-23 01:43 UTCEG score recompute
- 2026-10-23 01:43 UTCVendor advisory
- 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.4% · 29th percentile
- 2026-10-22 00:37 UTCEG score recompute
- 2026-10-22 00:37 UTCVendor advisory
- 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.4% · 29th percentile
- 2026-10-20 23:29 UTCEG score recompute
- 2026-10-20 23:29 UTCVendor advisory
- 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-19 22:24 UTCEG score recompute
- 2026-10-19 22:24 UTCVendor advisory
- 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-18 21:17 UTCEG score recompute
- 2026-10-18 21:17 UTCVendor advisory
- 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-18 03:38 UTCEG score recompute
- 2026-10-17 20:12 UTCEG score recompute
- 2026-10-17 20:12 UTCVendor advisory
- 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-16 19:05 UTCEG score recompute
- 2026-10-16 19:05 UTCVendor advisory
- 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-15 16:17 UTCEG score recompute
- 2026-10-15 16:17 UTCVendor advisory
- 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-14 10:21 UTCEG score recompute
- 2026-10-14 10:21 UTCVendor advisory
- 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-13 08:53 UTCEG score recompute
- 2026-10-13 08:53 UTCVendor advisory
- 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-12 16:04 UTCEG score recompute
- 2026-10-12 07:46 UTCVendor advisory
- 2026-10-11 19:46 UTCEG score recompute
- 2026-10-11 17:01 UTCEG score recompute
- 2026-10-11 14:26 UTCEG score recompute
- 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-09 10:58 UTCOSV refresh
- 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.4% · 28th percentile
- 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.4% · 27th percentile
- 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.4% · 27th percentile
- 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.4% · 27th percentile
- 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.4% · 27th percentile
- 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.4% · 27th percentile
- 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.4% · 27th percentile
- 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.3% · 18th percentile
- 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.3% · 18th percentile
- 2026-09-19 18:23 UTCEG score recompute
- 2026-09-19 18:23 UTCVendor advisory
- 2026-09-19 18:15 UTCEG score recompute
- 2026-09-19 18:15 UTCVendor advisory
- 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-11 20:40 UTCOSV refresh
- 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.2% · 15th percentile
- 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.2% · 15th percentile
Related CVEs(same product + same vendor + same CWE)
Same vendor
10 shownredhat:RHSA-2026:63327 · redhat:RHSA-2026:63385
Same CWE
10 shownCWE-287 · CWE-326
Frequently asked(5)
What is CVE-2026-45363?
When was the CVE record for CVE-2026-45363 published?
Is CVE-2026-45363 actively exploited?
What is the CVSS score of CVE-2026-45363?
How do I remediate CVE-2026-45363?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-45363
Is Your Infrastructure Affected by CVE-2026-45363?
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