TI-2026-21578 Aliases CVE-2026-27127 GHSA-gp2f-7wcm-5fhx

Craft CMS has Cloud Metadata SSRF Protection Bypass via DNS Rebinding

MEDIUM 64CWE-367Published 2026-02-24 · Updated 2026-02-28

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: High
Attack requirements: Present
Impact type: —
Confidentiality · integrity · availability: High · None · None
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.

Summary

Craft is a content management system (CMS). In versions 4.5.0-RC1 through 4.16.18 and 5.0.0-RC1 through 5.8.22, the SSRF validation in Craft CMS’s GraphQL Asset mutation performs DNS resolution separately from the HTTP request. This Time-of-Check-Time-of-Use (TOCTOU) vulnerability enables DNS rebinding attacks, where an attacker’s DNS server returns different IP addresses for validation compared to the actual request. This is a bypass of the security fix for CVE-2025-68437 that allows access to all blocked IPs, not just IPv6 endpoints. Exploitation requires GraphQL schema permissions for editing assets in the `<VolumeName>` volume and creating assets in the `<VolumeName>` volume. These permissions may be granted to authenticated users with appropriate GraphQL schema access and/or Public Schema (if misconfigured with write permissions). Versions 4.16.19 and 5.8.23 patch the issue.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00487 42nd percentileScored 2026-11-07

Public exploit Yes 2 exploit referencesTagged by NVD

Fix Fixed cms (craftcms): 4.16.19, 5.8.23craftcms/cms (Packagist): 5.8.23, 4.16.19

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Craft CMS	cms	4.5.0-RC1 to before 4.16.19; 5.0.0-RC1 to before 5.8.23	4.16.19, 5.8.23	Patch available	CNA
—	craftcms/cms (Packagist)	5.0.0-RC1 to before 5.8.23	5.8.23	Patch available	GHSA-gp2f-7wcm-5fhx
—	craftcms/cms (Packagist)	3.5.0 to before 4.16.19	4.16.19	Patch available	GHSA-gp2f-7wcm-5fhx

cms VendorCraft CMS Affected 4.5.0-RC1 to before 4.16.19; 5.0.0-RC1 to before 5.8.23 Fixed in 4.16.19, 5.8.23 Patch available CNA
craftcms/cms (Packagist) Vendor— Affected 5.0.0-RC1 to before 5.8.23 Fixed in 5.8.23 Patch available GHSA-gp2f-7wcm-5fhx
craftcms/cms (Packagist) Vendor— Affected 3.5.0 to before 4.16.19 Fixed in 4.16.19 Patch available GHSA-gp2f-7wcm-5fhx

CPE configurations NVD · 4

CPE	Versions	Role	Vendor
cpe:2.3:a:craftcms:craft_cms::::::::	3.5.1 to before 4.16.19; 5.0.1 to before 5.8.23	Vulnerable	Craft CMS
cpe:2.3:a:craftcms:craft_cms:3.5.0:-::::::	3.5.0	Vulnerable	Craft CMS
cpe:2.3:a:craftcms:craft_cms:5.0.0:-::::::	5.0.0	Vulnerable	Craft CMS
cpe:2.3:a:craftcms:craft_cms:5.0.0:rc1::::::	5.0.0 rc1	Vulnerable	Craft CMS

cpe:2.3:a:craftcms:craft_cms:*:*:*:*:*:*:*:* Versions 3.5.1 to before 4.16.19; 5.0.1 to before 5.8.23 Vulnerable ·Craft CMS
cpe:2.3:a:craftcms:craft_cms:3.5.0:-:*:*:*:*:*:* Versions 3.5.0 Vulnerable ·Craft CMS
cpe:2.3:a:craftcms:craft_cms:5.0.0:-:*:*:*:*:*:* Versions 5.0.0 Vulnerable ·Craft CMS
cpe:2.3:a:craftcms:craft_cms:5.0.0:rc1:*:*:*:*:*:* Versions 5.0.0 rc1 Vulnerable ·Craft CMS

Remediation

Fix · CNA cms (craftcms) Fixed in 4.16.19, 5.8.23
Fix · GHSA-gp2f-7wcm-5fhx craftcms/cms (Packagist) Fixed in 5.8.23 Advisory →
Fix · GHSA-gp2f-7wcm-5fhx craftcms/cms (Packagist) Fixed in 4.16.19 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2026-27127
2026-10-03 Alias added: GHSA-gp2f-7wcm-5fhx

References

Exploit 2

Patch 1

https://github.com/craftcms/cms/commit/a4cf3fb63bba3249cf1e2882b18a2d29e77a8575

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2026-27127

Other 6

TI-2025-23503 Craft CMS Allows Remote Code Execution KEVCVSS 3.1CRITICAL 10.0
TI-2024-37138 RCE when PHP `register_argc_argv` config setting is enabled in craftcms/cms KEVCVSS 4.0CRITICAL 9.3
TI-2025-16994 Potential RCE with a compromised security key in craft/cms KEVCVSS 3.1HIGH 8.1
TI-2025-24595 Craft CMS stores user-provided content in session files KEVCVSS 4.0MEDIUM 6.9
TI-2023-22284 Craft CMS Remote Code Execution vulnerability CVSS 3.1CRITICAL 10.0
TI-2024-25171 Craft CMS up to v3.7.31 was discovered to contain a SQL injection vulnerability via the GraphQL API endpoint. CVSS 3.1CRITICAL 9.8

See all 96 →

Sources

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