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CVE-2026-75866Suited to automated attack · CISA

Punk::OAuth2::Server versions through 0.03 for Perl issue access tokens outside a client's registered scopes and grant types because no authorization path reads them

CVSS score

9.1

EPSS probability

%0.5

Risk score

0.0

Published

1 mo ago

Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

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Vulnerability description

DayBreach CVE AI Research

CVE-2026-75866 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

Punk::OAuth2::Server versions through 0.03 for Perl issue access tokens outside a client's registered scopes and grant types because no authorization path reads them. Punk::OAuth2::Server::Store registers scopes and grant_types per client and documents both as client registration. token dispatches on the grant_type in the request body, so a client registered for authorization_code alone can ask for client_credentials, and that arm passes the requested scope straight to the minter, which signs it into the at+jwt access token. authorize copies the query scope into the authorization code record without comparing it against the registration, leaving the optional consent hook as the only check between an arbitrary scope and the issued code. redirect_uris on the same client row is read and enforced. A registered client can obtain a correctly signed token carrying any scope it names, and a resource server running Punk::OAuth2::Checker accepts that token and honours the scope. A client registered without a secret authenticates on its client_id alone, so anyone who knows that identifier can request one.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-75866 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1CPANSecPunk-OAuth2 View
Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
9.1CVSS V3_1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NCVE ADP
9.1CVSS V31CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-75866 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-75866 weaknesses.

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsGerekmiyor
UserGerekmiyor

Official Sources and Advisories

CVSS Vector Radar Chart

9.1 / 10
Attack VectorNetworkComplexityLowPrivilegesNoneUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityNone

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone required
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)None

Yama durumu bilinmiyor

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CPANSec logo
CPANSec

Weakness Type (CWE & CAPEC)

Similar Vulnerabilities

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