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CVE-2026-102946

Status: DeferredCritical (9.1)—
Severity9.1Critical · CVSS 3.1
Exploitation probability0.12 %higher than 2% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. Prior to 1.7.4, joserfc.jws.deserialize_json() accepts a JWS General JSON Serialization with an empty signatures array as authenticated. The verify_general_json() loop performs no iterations for the empty array and returns success because no signature check failed, allowing an attacker without a signing key to supply an arbitrary payload that relying applications may treat as authentic. The issue affects the General JSON Serialization path; compact JWS and JWT decoding, Flattened JSON serialization, and JWE JSON processing do not follow this vulnerable path. This issue is fixed in version 1.7.4.

CVSS

Base score
9.1
Version
3.1
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
0.12 %
Percentile among all scored CVEs
2
Score date
10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Vector AV:N/PR:N/UI:N; un JWS con array de firmas vacío se acepta como autenticado, permitiendo payloads arbitrarios sin clave (bypass de verificación de firma).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

ATT&CK mitigations that cover these techniques

Privileged Account ManagementNetwork SegmentationVulnerability ScanningRestrict File and Directory PermissionsRestrict Registry PermissionsOperating System Configuration

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Hsiaoming — JoserfcAI

CWEs

References

Show 4 references

Raw JSON (NVD)

Show
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