{"answers":{"affected":"5 open source packages ship an affected version, including github.com/caddyserver/caddy/v2 and github.com/caddyserver/caddy. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-52846 exists.","fix":"Upgrade github.com/caddyserver/caddy/v2 to 2.11.4 or later.","what":"CVE-2026-52846 is a medium-severity cross-site scripting vulnerability in caddyserver caddy, published on 23 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-52846 and fix it if it is affected.\n\nWhat it is: CVE-2026-52846 is a medium-severity cross-site scripting vulnerability in caddyserver caddy, published on 23 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-52846 exists.\n\nAffected packages and fixed versions:\n- github.com/caddyserver/caddy/v2 (Go): affected all versions; fixed in 2.11.4\n- github.com/caddyserver/caddy/v2 (Go): affected all versions; fixed in 2.11.4\n- github.com/caddyserver/caddy/v2 (Go): affected all versions; fixed in 2.11.4\n- github.com/caddyserver/caddy (Go): affected all versions up to 1.0.5; no fix listed\n- github.com/caddyserver/caddy (Go): affected all versions up to 1.0.5; no fix listed\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-52846/ (Markdown: https://insights.sbomify.com/CVE-2026-52846/index.md)","id":"CVE-2026-52846","markdown":"https://insights.sbomify.com/CVE-2026-52846/index.md","name":"CVE-2026-52846","record":{"aliases":["CLEANSTART-2026-UL03599","DEBIAN-CVE-2026-52846","GHSA-vcc4-2c75-vc9v","GO-2026-5660","MINI-p8cr-c9wg-wrmw","MINI-qvjv-hmf9-m25g","UBUNTU-CVE-2026-52846"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"Caddy web server","requires_auth":"none","summary":"Attackers can bypass HTML stripping to inject malicious scripts, leading to client-side XSS when untrusted data is rendered.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"caddy","vendor":"caddyserver"}],"cvss":{"score":4.2,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-116","name":"Improper Encoding or Escaping of Output"}],"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 \u003c\u003c\u003eimg src=x onerror=alert()\u003e, 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.","ecosystems":["Go"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Caddy: stripHTML template function bypass","id":"CVE-2026-52846","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Go","product":null,"products":[],"type":"xss","year":"2026"},"n_packages":5,"n_references":1,"next":{"headline":"Docmost: Broken access control in transclusion lookup API leaks sync-block content across private spaces","id":"CVE-2026-52850"},"packages":[{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":["1.0.5"],"package":"github.com/caddyserver/caddy","purl":null,"source":"GHSA-vcc4-2c75-vc9v"},{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":["1.0.5"],"package":"github.com/caddyserver/caddy","purl":"pkg:golang/github.com/caddyserver/caddy","source":"GHSA-vcc4-2c75-vc9v"},{"ecosystem":"Go","fixed":["2.11.4"],"introduced":["0"],"last_affected":[],"package":"github.com/caddyserver/caddy/v2","purl":null,"source":"GHSA-vcc4-2c75-vc9v"},{"ecosystem":"Go","fixed":["2.11.4"],"introduced":["0"],"last_affected":[],"package":"github.com/caddyserver/caddy/v2","purl":"pkg:golang/github.com/caddyserver/caddy/v2","source":"GHSA-vcc4-2c75-vc9v"},{"ecosystem":"Go","fixed":["2.11.4"],"introduced":["0"],"last_affected":[],"package":"github.com/caddyserver/caddy/v2","purl":"pkg:golang/github.com/caddyserver/caddy/v2","source":"GO-2026-5660"}],"prev":{"headline":"Caddy: FastCGI header normalization bypass in `forward_auth copy_headers`","id":"CVE-2026-52845"},"products":["caddy"],"published":"2026-06-23","related":[{"cvss_score":9.8,"headline":"Caddy vulnerable to Authentication Bypass due to mishandling of TLS client authentication","id":"CVE-2018-21246","kev_date_added":null,"published":"2020-06-15"},{"cvss_score":8.9,"headline":"Caddy: Unicode case-folding length expansion causes incorrect split_path index in FastCGI transport","id":"CVE-2026-27590","kev_date_added":null,"published":"2026-02-24"},{"cvss_score":8.8,"headline":"Caddy's mTLS client authentication silently fails open when CA certificate file is missing or malformed","id":"CVE-2026-27586","kev_date_added":null,"published":"2026-02-24"},{"cvss_score":8.1,"headline":"Caddy: Unsafe Unicode Handling in FastCGI splitPos Allows Execution of Non-PHP Files","id":"CVE-2026-45135","kev_date_added":null,"published":"2026-06-23"},{"cvss_score":8.1,"headline":"Caddy: FastCGI header normalization bypass in `forward_auth copy_headers`","id":"CVE-2026-52845","kev_date_added":null,"published":"2026-06-23"},{"cvss_score":8.1,"headline":"Caddy forward_auth copy_headers Does Not Strip Client-Supplied Headers, Allowing Identity Injection and Privilege Escalation","id":"CVE-2026-30851","kev_date_added":null,"published":"2026-03-07"},{"cvss_score":7.7,"headline":"Caddy: MatchPath %xx (escaped-path) branch skips case normalization, enabling path-based route/auth bypass","id":"CVE-2026-27587","kev_date_added":null,"published":"2026-02-24"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"Go Vulnerability Database","prefix":"GO"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-06-25","vendors":["caddyserver"]},"summary":"Attackers can bypass HTML stripping to inject malicious scripts, leading to client-side XSS when untrusted data is rendered.","url":"https://insights.sbomify.com/CVE-2026-52846/"}