CVE-2026-53944

mediumpriority · track · 0EPSS 0.003 · 26 %ileEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.33% (26th) EPSS
CVSS 5.8 · medium
Is it mine?
3 products
Check your exposure
Who says so?
3 sources
cnnvd · enisa_euvd · osv

EPSS · scored 2026-10-27

Ghost is a Node.js content management system. From 6.0.9 until 6.21.1, when making an external request, it is possible to bypass the IP filter that ensures the request isn't going to an internal service using an IPv6 literal which maps to a private IPv4 address. This vulnerability is fixed in 6.21.1.

01

cvss

Technical severity, 0–10. One row per scoring source.

5.8
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · ENISA EU
v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · security-advisories@github.comexploitability 3.9 · impact 1.4
v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · OSV
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-184USprimaryCWE-918USprimaryCWE-184USCWE-918US
04

affected products (3)

Products and version ranges known to be affected.

05

advisories (2)

Vendor and ecosystem advisories describing this.

  • GHSA-wvp2-4qqp-4h3rGhost: Private IP filtering bypass to make server-side requests to internal services2026-08-04ghsa · osvUS

    ### Impact When making an external request, it is possible to bypass the IP filter that ensures the request isn't going to an internal service using an IPv6 literal which maps to a private IPv4 address. ### Vulnerable versions This vulnerability is present in Ghost from v6.0.9 up to v6.21.0. ### Patches v6.21.1 contains a fix for this issue. ### How to update For self-hosters using Docker, find [Docker's official Ghost image here](https://hub.docker.com/_/ghost). Updating a Docker-based Ghost instance [is documented here](https://docs.ghost.org/install/docker#updating-ghost). If your Ghost is a Ghost-CLI install see our documentation on [updating it to the latest version here](https://docs.ghost.org/update). ### References Ghost thanks [l3tchupkt](http://github.com/l3tchupkt) for disclosing this vulnerability responsibly. ### For more information If you have any questions or comments about this advisory, email us at [security@ghost.org](mailto:security@ghost.org).

  • BIT-ghost-2026-53944Ghost: Private IP filtering bypass to make server-side requests to internal services2026-06-30vendor · osvUS

    Ghost is a Node.js content management system. From 6.0.9 until 6.21.1, when making an external request, it is possible to bypass the IP filter that ensures the request isn't going to an internal service using an IPv6 literal which maps to a private IPv4 address. This vulnerability is fixed in 6.21.1.

06

also known as (5)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdosvNVDCVE.orgMITRE
published 2026-06-24modified 2026-10-25
09

references (3)

External citations — patches, advisories, analysis.

scry

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