CVE-2026-56708Network attack vector

Internal service access via DNS rebinding

Published Aug 25, 2026 · Updated Aug 25, 2026

SSRF in the Grav API plugin before 1.0.16 allows remote authenticated users to reach internal services through webhook delivery. WebhookDispatcher::httpPost validates a DNS answer but discards it, then lets cURL resolve the hostname again for the connection. Exploitation requires api.webhooks.write permission, authoritative DNS control, a low TTL, and winning the lookup race; configured headers and body reach the target, with limited response read-back.

CVSS severity6.9
Medium
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SSRF in the Grav API plugin before 1.0.16 allows remote authenticated users to reach internal services through webhook delivery. WebhookDispatcher::httpPost validates a DNS answer but discards it, then lets cURL resolve the hostname again for the connection. Exploitation requires api.webhooks.write permission, authoritative DNS control, a low TTL, and winning the lookup race; configured headers and body reach the target, with limited response read-back.

The record

CVE
CVE-2026-56708
Published
Aug 25, 2026
Updated
Aug 25, 2026
Vendor
GetGrav
Product
Grav
Classifications
CWE-367
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 25, 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 <1.0.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

GetGrav · Gravversion=0 <1.0.16

Published CVSS scores

5.3VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
6.9VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition

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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