What is CVE-2026-103277?

CVE-2026-103277 is a high-severity vulnerability in Tryghost Ghost, classified under Cross-site Scripting. CVSS score: 8.1/10. Published 2026-10-01.

How severe is CVE-2026-103277?

High severity. CVSS v3 base score is 8.1 out of 10.

XSS in Tryghost Ghost

CVE-2026-103277

Ghost versions from 2.5.0 before 6.34.0 contain an untrusted script execution vulnerability in the oEmbed preview feature that fails to sandbox externally hosted scripts. Attackers can craft malicious oEmbed content to execute scripts in the context of a staff user's admin session, potentially compromising administrative access.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-10-01.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Tryghost Ghost

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/TryGhost/Ghost/security/advisories/GHSA-8vhf-xxpj-4qrg (vendor-advisory)
www.vulncheck.com/advisories/ghost-2.5.0-before-6.34.0-untrusted-script-executi… (third-party-advisory)

Frequently asked questions

What is CVE-2026-103277?: CVE-2026-103277 is a high-severity vulnerability in Tryghost Ghost, classified under Cross-site Scripting. CVSS score: 8.1/10. Published 2026-10-01.
How severe is CVE-2026-103277?: High severity. CVSS v3 base score is 8.1 out of 10.