High Authentication

CVE-2026-59358 — UAA OAuth Token Endpoint Vulnerability allows user access token reuse for client_credentials grant type

Improper authentication (CWE-287) in the OAuth token endpoint in Cloud Foundry UAA allows a remote, authenticated attacker holding a valid user access token to obtain a fully-privileged client_credentials token for the OAuth client that issued it, by presenting the user token as an OAuth 2.0 Bearer credential on a client_credentials grant request in place of the client’s configured secret. UAA’s client_credentials handling does not verify that the Bearer credential supplied for client authentication is actually a client credential (a client secret or a valid configured client authentication method); it accepts any valid access token whose client_id matches the request. A token obtained by a normal end user through a public authorization_code + PKCE flow — scoped only to uaa.user, carrying a user_id, and recording client_auth_method=none — satisfies this check. That user token cannot itself administer OAuth clients (POST /oauth/clients correctly returns 403), but when replayed as Bearer authentication on a client_credentials request for the same client, UAA issues a new client-only token carrying the client’s full authorities, such as clients.write. An attacker can use that token to create arbitrary new OAuth clients, including clients with attacker-chosen authorities, without ever possessing the client’s actual secret. Exploitation requires a valid user access token (the attacker’s own) for a client that is configured to support both a public, user-facing authorization flow and the client_credentials grant type on the same client_id — a non-default combination. Practical impact scales with the authorities assigned to that client.

Published Oct 6, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: vmware

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.3% (30-day exploitation probability)+4
Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.35%

ahead of 26% of scored CVEs · Oct 14, 2026

Affects

Cloud Foundry Foundation

Cf-deployment and 1 more

CVSS base

7.6

High · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Total

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Cloud Foundry Foundation Cf-deployment, Cloud Foundry Foundation UAA).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes matching the vulnerability class (authentication), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Cloud Foundry Foundation	Cf-deployment	≤ 60.4.0	Vulnerable	CVE Program (cve.org) e CISA ADP
Cloud Foundry Foundation	UAA	≥ 3.7.0 and ≤ 79.6.0	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Attack requirements

Present

Privileges required

Low

User interaction

None

Scope

Confidentiality (vulnerable system)

High

Integrity (vulnerable system)

High

Availability (vulnerable system)

None

Confidentiality (subsequent)

None

Integrity (subsequent)

None

Availability (subsequent)

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
7.6	CVSS 4.0	High	—	—	security@vmware.com via NIST National Vulnerability Database
7.6	CVSS 4.0	High	—	—	vmware via CVE Program (cve.org) e CISA ADP

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

(score shown at the top: security@vmware.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-287 · Improper Authentication

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.35%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Review authentication logs: logins without MFA, anomalous sessions and recently created accounts.

web/proxy/WAF logsnetwork IDS/IPSauthentication logs

Timeline

What happened to this CVE, newest first.

2026
Affected products added · cloud foundry/uaa, cloud foundry/cf-deployment
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
CVSS changed · 7.6
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Awaiting Analysis
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Oct 6, 2026 · vmware

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

www.cloudfoundry.org/blog/cve-2026-59358-uaa-oauth-token-endpoint-vulnerability-allows-use
NIST National Vulnerability Database

Elsewhere on this site

Cloud Foundry Foundation
every CVE for this vendor

Authentication
same class

CWE-287
other pages naming this weakness

Related CVEs (same products)

Medium CVE-2026-59357 Self-UAA OIDC Configuration allows JWT injection to establish unauthorized sessions 9d
High CVE-2026-47840 LDAP StartTLS unconditionally disables hostname verification Jul 9, 2026
Critical CVE-2026-41005 UAA accepts SAML Encrypted Assertions authentication bypass Jun 11, 2026
High CVE-2026-40964 Improper Authentication in Cloud Foundry Foundation Log-cache Release Jun 1, 2026
Critical CVE-2026-40965 Exposure of Sensitive Information in Cloud Foundry Foundation Uaa-release Jun 1, 2026
High CVE-2026-41013 Tenant-controlled comma smuggles arbitrary CIFS mount options Jun 1, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-59358 is "UAA OAuth Token Endpoint Vulnerability allows user access token reuse for client_credentials grant type", rated High. It affects Cf-deployment (Cloud Foundry Foundation); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.6 describes technical severity. EPSS 0.35% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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