CVE-2026-22734Network attack vector

Unauthenticated token impersonation via unsigned SAML assertions

Published Apr 16, 2026 · Updated Apr 16, 2026

Authentication bypass in Cloud Foundry UAA 77.21.0 through 78.8.0 allows remote attackers to obtain tokens for arbitrary users. The SAML 2.0 bearer grant accepts assertions carrying neither a signature nor encryption and treats supplied identities as authenticated. Exposure requires SAML 2.0 bearer assertions to be enabled for a client; issued tokens grant access to UAA-protected systems as the impersonated user.

CVSS severity8.8
High
EPSS probability0.36%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Cloud Foundry UAA 77.21.0 through 78.8.0 allows remote attackers to obtain tokens for arbitrary users. The SAML 2.0 bearer grant accepts assertions carrying neither a signature nor encryption and treats supplied identities as authenticated. Exposure requires SAML 2.0 bearer assertions to be enabled for a client; issued tokens grant access to UAA-protected systems as the impersonated user.

The record

CVE
CVE-2026-22734
Published
Apr 16, 2026
Updated
Apr 16, 2026
Vendor
Cloud Foundry Foundation
Product
User Account and Authentication (UAA)
Classifications
CWE-290, CAPEC-646, T1606.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 16, 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=v77.21.0 <=v78.8.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Cloud Foundry Foundation · User Account and Authentication (UAA)version=v77.21.0 <=v78.8.0

Published CVSS scores

8.6Cloud Foundry FoundationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
8.8Cloud Foundry FoundationCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:L/SI:L/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.

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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 exploitUnconfirmed

Weakness, pattern, technique

CWE-290Authentication Bypass by Spoofing
CAPEC-646Peripheral Footprinting
T1606.002Forge Web Credentials: SAML Tokens

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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