CVE-2026-102268

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2% (8th percentile of EPSS-scored CVEs). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 4 sources updated this weekElevated
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 9.1Exploit: Elevated riskExposed services: Not assessed

A fix is available — apply it.

PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, is_pem_format in jwt/utils.py is affected because is_pem_format does not recognize every PEM representation accepted by the cryptography loader. This occurs when an application mixes HMAC and asymmetric algorithms and supplies a mutated public-key PEM as raw key bytes. As a result, HMACAlgorithm.prepare_key treats the unrecognized asymmetric public key as an HMAC secret. Consequently, an attacker who knows the public key can forge authenticated HMAC tokens. This issue is fixed in version 2.14.0.

CVSS v3
9.1
EG Score
9.1CRITICALmedium confidence
EG Risk
72
EG Risk 72/100CISA SSVC

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
Severity91% × 45%
Exploitation40% × 40%
Automatability100% × 15%
CISA SSVC: Track at low, Track* at medium and Attend at high mission impact.
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
0.2%
EPSS %ILE
8th
KEV
Not listed

CISA SSVCTrack at low, Track* at medium and Attend at high mission impact.

A fix is available. Apply it within your standard update timelines 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). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 28, 2026

Last Modified

September 30, 2026

Advisory Details (3)

Auto-updated Sep 28, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github_release, github.
github_release Patch Available

2.14.0

Patch available: jpadilla/pyjwt 2.14.0

https://github.com/jpadilla/pyjwt/releases/tag/2.14.0
github_commit Patch Available

commit 8b4e233a2220 (jpadilla/pyjwt)

Patch available: jpadilla/pyjwt 2.14.0 (contains commit 8b4e233a2220)

https://github.com/jpadilla/pyjwt/commit/8b4e233a22206b34ec1186e912e75c0b2396ac07
github Patch Available🟡 PoC Available

Asymmetric-PEM detection bypass: whitespace/line-ending-mutated public keys skip the HS/asymmetric confusion guard, permitting HS256 token forgery under a mixed algorithm allow-list. · Advisory · jpadilla/pyjwt · GitHub

https://github.com/jpadilla/pyjwt/security/advisories/GHSA-ffc3-869f-jxw9

Vendor Advisories for CVE-2026-102268(2)

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)
PyPI(1)
PackageVulnerable rangeFixed inDependents
pyjwt0.1.1 ... 2.9.0 (55 versions)2.14.0—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 39× in last 7d / 39× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.

  1. 2026-10-04 09:32 UTCVendor advisory
  2. 2026-10-04 05:15 UTCVendor advisory
  3. 2026-10-04 00:59 UTCVendor advisory
  4. 2026-10-03 20:44 UTCVendor advisory
  5. 2026-10-03 16:24 UTCEG score recompute
  6. 2026-10-03 16:24 UTCVendor advisory
  7. 2026-10-03 14:25 UTCEPSS rescore
  8. 2026-10-03 12:07 UTCVendor advisory
  9. 2026-10-03 07:51 UTCVendor advisory
  10. 2026-10-03 03:32 UTCVendor advisory
  11. 2026-10-02 23:16 UTCVendor advisory
  12. 2026-10-02 18:58 UTCEG score recompute
  13. 2026-10-02 18:58 UTCVendor advisory
  14. 2026-10-02 14:42 UTCVendor advisory
  15. 2026-10-02 10:25 UTCVendor advisory
  16. 2026-10-02 06:10 UTCVendor advisory
  17. 2026-10-02 01:54 UTCVendor advisory
  18. 2026-10-01 21:38 UTCEG score recompute
  19. 2026-10-01 21:38 UTCVendor advisory
  20. 2026-10-01 19:49 UTCEPSS rescore
  21. 2026-10-01 17:19 UTCVendor advisory
  22. 2026-10-01 13:01 UTCVendor advisory
  23. 2026-10-01 08:46 UTCVendor advisory
  24. 2026-10-01 04:30 UTCVendor advisory
  25. 2026-10-01 00:14 UTCVendor advisory
Show 14 more
  1. 2026-09-30 19:44 UTCVendor advisory
  2. 2026-09-30 16:57 UTCEG score recompute
  3. 2026-09-30 16:57 UTCVendor advisory
  4. 2026-09-30 15:02 UTCEPSS rescore
  5. 2026-09-30 12:41 UTCVendor advisory
  6. 2026-09-30 08:24 UTCVendor advisory
  7. 2026-09-29 18:37 UTCEG score recompute
  8. 2026-09-29 15:20 UTCEPSS rescore
  9. 2026-09-29 14:19 UTCEG score recompute
  10. 2026-09-29 14:04 UTCEG score recompute
  11. 2026-09-29 01:33 UTCEG score recompute
  12. 2026-09-28 21:18 UTCEG score recompute
  13. 2026-09-28 20:36 UTCEG score recompute
  14. 2026-09-28 20:36 UTCMITRE cvelistV5first tracked

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2026-102268?
CVE-2026-102268 is a critical vulnerability published on September 28, 2026. PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, ispemformat in jwt/utils.py is affected because ispemformat does not recognize every PEM representation accepted by the cryptography loader. This occurs when an application mixes HMAC and asymmetric algorithms and…
When was CVE-2026-102268 disclosed?
CVE-2026-102268 was first published on September 28, 2026, with the most recent update on September 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-102268 actively exploited?
CVE-2026-102268 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (8th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-102268?
CVE-2026-102268 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-2026-102268?
A fix for CVE-2026-102268 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-102268 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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