CVE-2026-52769Public exploitNetwork attack vector

Unauthenticated internal service probing via signature key URL

Published Sep 4, 2026 · Updated Sep 4, 2026

SSRF in YesWiki 4.6.2 through 4.6.5 allows remote attackers to make arbitrary HTTP requests through the ActivityPub inbox route. HttpSignatureService::verifySignature() parses the attacker-controlled Signature keyId and fetches that URL before validating its destination or verifying the signature. ActivityPub must be enabled on a Bazar form; exposed servers allow internal-service and cloud-metadata probing through timing and error responses.

CVSS severity8.3
High
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SSRF in YesWiki 4.6.2 through 4.6.5 allows remote attackers to make arbitrary HTTP requests through the ActivityPub inbox route. HttpSignatureService::verifySignature() parses the attacker-controlled Signature keyId and fetches that URL before validating its destination or verifying the signature. ActivityPub must be enabled on a Bazar form; exposed servers allow internal-service and cloud-metadata probing through timing and error responses.

The record

CVE
CVE-2026-52769
Published
Sep 4, 2026
Updated
Sep 4, 2026
Vendor
YesWiki
Product
YesWiki
Classifications
CWE-918, T1046, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 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=>= 4.6.2, < 4.6.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

YesWiki · YesWikiversion=>= 4.6.2, < 4.6.6

Published CVSS scores

8.3GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L

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)
T1046Network Service Discovery
T1190Exploit Public-Facing Application

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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