CVE-2026-73497Public exploitNetwork attack vectorHinoki check available

Unauthenticated SSRF via DNS-rebinding IP re-resolution

Published Sep 14, 2026 · Updated Sep 14, 2026

SSRF in MCP Atlassian 0.17.0 through 0.21.1 allows remote attackers to access cloud metadata or internal services via crafted headers. The URL validator approves each header hostname once, discards the resolved IP, and later connects through the raw hostname, causing an unpinned second DNS lookup. Exploitation requires an attacker-controlled rebinding DNS name to change answers between validation and connection; successful requests can read metadata credentials or reach otherwise inaccessible internal services.

CVSS severityUnavailable
Unscored
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

SSRF in MCP Atlassian 0.17.0 through 0.21.1 allows remote attackers to access cloud metadata or internal services via crafted headers. The URL validator approves each header hostname once, discards the resolved IP, and later connects through the raw hostname, causing an unpinned second DNS lookup. Exploitation requires an attacker-controlled rebinding DNS name to change answers between validation and connection; successful requests can read metadata credentials or reach otherwise inaccessible internal services.

The record

CVE
CVE-2026-73497
Published
Sep 14, 2026
Updated
Sep 14, 2026
Vendor
sooperset
Product
MCP Atlassian
Classifications
CWE-918, CWE-367, T1190, T1552.005
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 14, 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=>= 0.17.0, < 0.22.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

sooperset · MCP Atlassianversion=>= 0.17.0, < 0.22.0

Published CVSS scores

No CVSS assessment is available in this record.

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-918Server-Side Request Forgery (SSRF)
CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition
T1190Exploit Public-Facing Application
T1552.005Unsecured Credentials: Cloud Instance Metadata API

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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