CVE-2026-27166 is a medium-severity vulnerability (CVSS 5.4) affecting Discourse versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2. The flaw, stemming from insufficient cleanup in the default Codepen allowed iframes, enables an attacker to trick a user into changing the main page URL. This network-based attack requires user interaction and could lead to low confidentiality and integrity impacts. Currently, there is no evidence of active exploitation, public exploit code availability, or significant community discussion or media coverage.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 2026.3.0CPE matchmatch criteria | cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:* | ||
>= 2026.1.0, < 2026.1.2CPE matchmatch criteria | cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:* | ||
>= 2026.2.0, < 2026.2.1CPE matchmatch criteria | cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:* | ||
2026.3.0CPE matchmatch criteria | cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.