CVE-2026-48522

MEDIUMPre-NVD 4.24.2—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 4.2 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 87% of all CVEs by exploit prediction. 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
Elevated
4.2EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.2Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, PyJWKClient passes its uri argument directly to urllib.request.urlopen() which uses Python stdlib's default OpenerDirector registering HTTPHandler, HTTPSHandler, FTPHandler, FileHandler, and DataHandler. There is currently no documented option to restrict which schemes PyJWKClient will fetch. If an application's jku URL ingestion path accepts attacker-influenced URLs (e.g., from JWT header, configuration file, OAuth flow parameter), the attacker can cause PyJWKClient to read arbitrary local files via file:// (SSRF on local filesystem), cause PyJWKClient to attempt FTP / data-URI fetches (broader SSRF surface), or forge tokens that PyJWT verifies as valid. The library does not directly return non-HTTP(S) URI contents to the attacker; the chained "plant a JWKS to forge tokens" scenario described in the original report requires additional application-layer flaws (attacker write access to a filesystem path, untrusted jku derivation) that this fix does not address. This vulnerability is fixed in 2.13.0.

CVSS v3
4.2
EG Score
4.2(medium)
EG Risk
35(Track)
EG Risk 35/100SSVC: Track

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
Severity42% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
13%
KEV
Not listed

Published

May 28, 2026

Last Modified

June 2, 2026

Advisory Details (1)

Auto-updated Jun 15, 2026
Patch available. Sources: github.
github Patch Available

PyJWKClient: missing scheme allowlist enables CVE-2024-21643-class SSRF + token forgery via file://, ftp://, data: schemes · Advisory · jpadilla/pyjwt · GitHub

https://github.com/jpadilla/pyjwt/security/advisories/GHSA-993g-76c3-p5m4

Vendor Advisories for CVE-2026-48522(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 (54 versions)2.13.0—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 32× 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. 2026-07-27 09:40 UTCEG score recompute
  2. 2026-07-26 14:54 UTCEPSS rescore
  3. 2026-07-25 14:18 UTCEPSS rescore
  4. 2026-07-24 14:18 UTCEPSS rescore
  5. 2026-07-23 14:18 UTCEPSS rescore
  6. 2026-07-23 03:18 UTCEG score recompute
  7. 2026-07-22 14:08 UTCEPSS rescore
  8. 2026-07-21 15:25 UTCEPSS rescore
  9. 2026-07-20 17:08 UTCEPSS rescore
  10. 2026-07-19 14:31 UTCEPSS rescore
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  1. 2026-07-01 15:07 UTCEPSS rescore
  2. 2026-06-30 23:22 UTCEPSS rescore
  3. 2026-06-29 14:06 UTCEPSS rescore
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  5. 2026-06-28 14:07 UTCEPSS rescore
  6. 2026-06-28 04:56 UTCEPSS rescore
  7. 2026-06-28 04:56 UTCEPSS rescore
  8. 2026-06-27 03:08 UTCEPSS rescore
  9. 2026-06-25 13:49 UTCEPSS rescore
  10. 2026-06-24 14:05 UTCEPSS rescore
  11. 2026-06-23 21:33 UTCEPSS rescore
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  13. 2026-06-22 14:25 UTCEPSS rescore
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  15. 2026-06-21 14:56 UTCEPSS rescore
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  17. 2026-06-21 01:59 UTCEPSS rescore
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  19. 2026-06-19 19:26 UTCEPSS rescore
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  21. 2026-06-18 17:52 UTCEPSS rescore
  22. 2026-06-18 17:52 UTCEPSS rescore
  23. 2026-06-17 17:53 UTCEPSS rescore
  24. 2026-06-16 17:53 UTCEPSS rescore
  25. 2026-06-15 17:49 UTCEPSS rescore
  26. 2026-06-15 17:49 UTCEPSS rescore
  27. 2026-06-14 23:18 UTCEPSS rescore
  28. 2026-06-13 23:00 UTCEPSS rescore
  29. 2026-06-12 23:12 UTCEPSS rescore
  30. 2026-06-12 23:12 UTCEPSS rescore
  31. 2026-06-11 14:00 UTCEPSS rescore
  32. 2026-06-10 22:18 UTCEPSS rescore
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  35. 2026-06-08 14:17 UTCEPSS rescore
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  37. 2026-06-07 15:25 UTCEPSS rescore
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  39. 2026-06-06 13:47 UTCEPSS rescore
  40. 2026-06-06 13:47 UTCEPSS rescore
  41. 2026-06-05 22:47 UTCEPSS rescore
  42. 2026-06-05 06:10 UTCEPSS rescore
  43. 2026-06-05 06:10 UTCEPSS rescore
  44. 2026-06-04 13:12 UTCEPSS rescore
  45. 2026-06-04 13:12 UTCEPSS rescore
  46. 2026-06-02 20:13 UTCEPSS rescore
  47. 2026-06-01 13:52 UTCEPSS rescore
  48. 2026-06-01 13:52 UTCEPSS rescore
  49. 2026-05-31 22:30 UTCEPSS rescore
  50. 2026-05-31 22:30 UTCEPSS rescore
  51. 2026-05-31 00:16 UTCEPSS rescore
  52. 2026-05-31 00:16 UTCEPSS rescore
  53. 2026-05-29 13:44 UTCEPSS rescore
  54. 2026-05-29 13:44 UTCEPSS rescore
  55. 2026-05-28 15:26 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-48522?
CVE-2026-48522 is a medium vulnerability published on May 28, 2026. PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, PyJWKClient passes its uri argument directly to urllib.request.urlopen() which uses Python stdlib's default OpenerDirector registering HTTPHandler, HTTPSHandler, FTPHandler, FileHandler, and DataHandler. There is currently no…
When was CVE-2026-48522 disclosed?
CVE-2026-48522 was first published in the National Vulnerability Database on May 28, 2026, with the most recent update on June 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-48522 actively exploited?
CVE-2026-48522 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 87.1% of all scored CVEs.
What is the CVSS score of CVE-2026-48522?
CVE-2026-48522 has a CVSS v3 base score of 4.2 (NVD).
How do I remediate CVE-2026-48522?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-48522, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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