Medium severity · published Jun 23, 2026
CVE-2026-52846
Caddy: stripHTML template function bypass
4.2
CVSS
0.2%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CA
caddy · caddyserver
< 2.11.4 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-52846
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-52846
Exploit
https://github.com/caddyserver/caddy/security/advisories/GHSA-vcc4-2c75-vc9v
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