CVE-2026-77775Network attack vector

Internal data disclosure via client-selected upstream

Published Aug 21, 2026 · Updated Aug 21, 2026

SSRF in Headroom Labs Headroom before 0.36.1 allows remote attackers to read internal-service responses through a client-selected upstream. The OpenAI and passthrough proxy routes accept x-headroom-base-url after checking only for an HTTP(S) scheme and hostname, then forward the request and its Authorization header without excluding private or metadata addresses. The CLI binds to loopback by default, but the shipped Docker Compose configuration publishes unauthenticated data-plane routes, exposing internal responses and forwarded credentials to network clients.

CVSS severity8.6
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

SSRF in Headroom Labs Headroom before 0.36.1 allows remote attackers to read internal-service responses through a client-selected upstream. The OpenAI and passthrough proxy routes accept x-headroom-base-url after checking only for an HTTP(S) scheme and hostname, then forward the request and its Authorization header without excluding private or metadata addresses. The CLI binds to loopback by default, but the shipped Docker Compose configuration publishes unauthenticated data-plane routes, exposing internal responses and forwarded credentials to network clients.

The record

CVE
CVE-2026-77775
Published
Aug 21, 2026
Updated
Aug 21, 2026
Vendor
Headroom Labs
Product
Headroom
Classifications
CWE-918, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 21, 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=0 <0.36.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Headroom Labs · Headroomversion=0 <0.36.1

Published CVSS scores

8.6VulnCheck CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
7.7VulnCheck CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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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