Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.9.1, Authlib's OctKey.import_key() and HMAC signing and verification path accept zero-length key material. If an application's secret lookup can return an empty string or empty bytes, a remote attacker can compute the deterministic HS256, HS384, or HS512 signature for arbitrary token claims and have Authlib treat the token as authentic. This issue is fixed in version 1.9.1.
CVE-2026-114616
“—” beside the score: it is equal to NVD's CVSS score.
This critical-severity CVE scores 9.1 under NVD CVSS v3. EPSS exploit probability: 0.3% (22nd 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 2026-10-27) is not newer than that change (2026-10-30), so it does not.
Also known asEUVD-2026-108517 (ENISA EUVD) · GHSA-8m4g-j4wp-wgcg (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
- 41EG Risk 41/100
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.Exploitation0.3% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).Exploitation none (CISA Vulnrichment) · Automatable no (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. - EPSS PROB
- 0.3%
- EPSS %ILE
- 22nd
- 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.NVD CVSS v3 · CVSS v3.0 or v3.1
- EG Likelihood
- 0.3% 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 or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade 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; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (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)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (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
October 22, 2026
Last Modified
October 30, 2026
Advisory Details (3)
Auto-updated Oct 22, 2026v1.9.1
Patch available: authlib/authlib v1.9.1
https://github.com/authlib/authlib/releases/tag/v1.9.1commit 4ff30db442c7 (authlib/authlib)
Patch available: authlib/authlib v1.9.1 (contains commit 4ff30db442c7)
https://github.com/authlib/authlib/commit/4ff30db442c70e29486e1982cb0ad37c037f5f4bAuthlib accepts an empty HMAC key, allowing JWS/JWT signature forgery (HS256/HS384/HS512) · Advisory · authlib/authlib · GitHub
https://github.com/authlib/authlib/security/advisories/GHSA-8m4g-j4wp-wgcgVendor Advisories for CVE-2026-114616(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Patch Availability(3)
| Vendor / Ecosystem | Fix (by version range) / Patch | Released | Source |
|---|---|---|---|
| redhat | satellite/foreman-mcp-server-rhel9:1793272276 | 2026-10-29 | redhat |
| redhat | satellite/foreman-mcp-server-rhel9:1793272279 | 2026-10-29 | redhat |
| pip | Authlib @ 1.9.1 (fixes < 1.9.1) | — | 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
(1 across 1 ecosystem)
PyPI(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| authlib | 0.1 ... 1.9.0 (65 versions) |
| — |
Weakness Classification(3)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
All Vendor Advisories
(2)
Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.
Data Freshness Timeline
(refreshed 18× in last 7d / 26× 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.
- 2026-11-01 18:50 UTCEG score recompute
- 2026-11-01 18:50 UTCVendor advisory
- 2026-11-01 18:50 UTCGHSA enrichmentGHSA-8m4g-j4wp-wgcg · GitHub severity HIGH · GitHub CVSS 7.4
- 2026-11-01 16:33 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
- 2026-11-01 07:59 UTCGHSA enrichmentGHSA-8m4g-j4wp-wgcg · GitHub severity HIGH · GitHub CVSS 7.4
- 2026-11-01 07:59 UTCEG score recompute
- 2026-10-31 19:38 UTCEG score recompute
- 2026-10-31 19:38 UTCVendor advisory
- 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
- 2026-10-30 20:14 UTCEG score recompute
- 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
- 2026-10-30 14:18 UTCEG score recompute
- 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
- 2026-10-29 15:06 UTCEG score recompute▲ 1.70
- 2026-10-29 15:06 UTCNVD updateCVSS v3 → 9.1 · severity → CRITICAL
- 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.2% · 11th percentile
- 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.2% · 11th percentile
- 2026-10-26 16:30 UTCEPSS rescoreEPSS 0.2% · 11th percentile
- 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.2% · 11th percentile
- 2026-10-25 14:50 UTCEG score recompute
- 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.2% · 10th percentile
- 2026-10-23 19:47 UTCEG score recompute
- 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.2% · 10th percentile
- 2026-10-22 22:28 UTCEG score recompute
- 2026-10-22 21:28 UTCEG score recomputeFirst assessed: 7.4 HIGH
Show 1 moreShow fewer
- 2026-10-22 21:25 UTCMITRE cvelistV5first tracked
Related CVEs(same product + same vendor + same CWE)
Same product
10 shownPyPI:authlib
Same vendor
8 shownredhat:RHSA-2026:92666
Frequently asked(5)
What is CVE-2026-114616?
When was the CVE record for CVE-2026-114616 published?
Is CVE-2026-114616 actively exploited?
What is the CVSS score of CVE-2026-114616?
How do I remediate CVE-2026-114616?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-114616
Is Your Infrastructure Affected by CVE-2026-114616?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.