CVE-2026-75759Public exploitNetwork attack vectorHinoki check available

User impersonation via unsigned encrypted identity tokens

Published Aug 30, 2026 · Updated Aug 30, 2026

Signature verification bypass in oidcc 3.2.0-beta.1 through 3.8.0 allows remote attackers to impersonate arbitrary users via encrypted tokens. oidcc_jwt_util:verify_decrypted_token/4 parsed unsigned decrypted claims as success, and oidcc_token:int_validate_jwt/4 trusted the JWE type instead of verified-signature state. Exploitation requires advertised ID-token or JARM encryption and a configured relying-party encryption key; forged claims then enable account takeover.

CVSS severity7.6
High
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Signature verification bypass in oidcc 3.2.0-beta.1 through 3.8.0 allows remote attackers to impersonate arbitrary users via encrypted tokens. oidcc_jwt_util:verify_decrypted_token/4 parsed unsigned decrypted claims as success, and oidcc_token:int_validate_jwt/4 trusted the JWE type instead of verified-signature state. Exploitation requires advertised ID-token or JARM encryption and a configured relying-party encryption key; forged claims then enable account takeover.

The record

CVE
CVE-2026-75759
Published
Aug 30, 2026
Updated
Aug 30, 2026
Vendor
Erlang Ecosystem Foundation
Product
oidcc
Classifications
CWE-347, CAPEC-475, T1606
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 30, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 30, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.2.0-beta.1 <3.9.0
  2. Affected versionversion=37a1361f704889816db2873f72d744d63ec39568 <5f62fbccdae8526ff62653b8901657a6c1400fd9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Erlang Ecosystem Foundation · oidccversion=3.2.0-beta.1 <3.9.0; version=37a1361f704889816db2873f72d744d63ec39568 <5f62fbccdae8526ff62653b8901657a6c1400fd9

Published CVSS scores

7.6Erlang Ecosystem FoundationCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature
CAPEC-475Signature Spoofing by Improper Validation
T1606Forge Web Credentials

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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