CVE-2026-52846

What it is

Caddy is an extensible server platform that uses TLS by default. Prior to 2.11.4, Caddy’s stripHTML template function cannot reliably remove all HTML tags from input strings. Certain malformed HTML, such as <<>img src=x onerror=alert()>, can bypass the tag-stripping logic, potentially leaving dangerous content in the output if it is later rendered as HTML. This may allow client-side XSS in cases where untrusted strings are rendered unsafely. This vulnerability is fixed in 2.11.4.

At a glance

Exploitability

Can be exploited over the network without logging in, but needs a user to act. Limited direct impact.

Exploit odds

0.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-06-23 18:18 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-29 19:08 UTC Last updatedMost recent change to the record

Details

Published

2026-06-23 18:18 UTC

Last modified

2026-06-29 19:08 UTC

Exploit probability

0.2% · EPSS, next 30 days

Weakness

CWE-116

Record status

Analyzed

Affected

• Caddyserver Caddy < 2.11.4

Attack profile CVSS 3.1 · 4.2

Attack vector

Network

Complexity

High

Privileges needed

None

User interaction

Required

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None