{"answers":{"affected":"It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73254 exists.","fix":"Upgrade to a fixed version.","what":"CVE-2026-73254 is a medium-severity cross-site scripting vulnerability in Cesanta Mongoose, published on 20 Aug 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-2026-73254 and fix it if it is affected.\n\nWhat it is: CVE-2026-73254 is a medium-severity cross-site scripting vulnerability in Cesanta Mongoose, published on 20 Aug 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-2026-73254 exists.\n\nAffected product: Cesanta Mongoose. No package-level version data is available, so check the vendor advisory linked from the reference page.\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-2026-73254/ (Markdown: https://insights.sbomify.com/CVE-2026-73254/index.md)","id":"CVE-2026-73254","markdown":"https://insights.sbomify.com/CVE-2026-73254/index.md","name":"CVE-2026-73254","record":{"aliases":["DEBIAN-CVE-2026-73254","GHSA-5g6j-m3pv-4f7g","JLSEC-2026-1378","UBUNTU-CVE-2026-73254"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["account_takeover","data_read"],"network_reachable":"yes","non_default_config":true,"product_category":"Mongoose web server","requires_auth":"none","summary":"Attackers can inject scripts via filenames in directory listings, allowing session theft or victim actions in Mongoose web servers.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"mongoose","vendor":"cesanta"}],"cvss":{"score":5.4,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"}],"description":"Mongoose is an embedded web server and network library. Prior to 7.22, an attacker who can create a file with an HTML payload in its name can trigger stored cross-site scripting when a user browses a directory served with MG_ENABLE_DIRLIST. The printdirentry() path called by listdir() in src/http.c URL-encodes the href but inserts the raw filesystem filename into the HTML link text. The browser executes the injected markup in the Mongoose origin, which can expose session data or permit actions as the victim. This issue is fixed in version 7.22.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Mongoose: Stored XSS via unescaped filenames in directory listing","id":"CVE-2026-73254","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"cesanta:mongoose","products":["cesanta:mongoose"],"type":"xss","year":"2026"},"n_packages":0,"n_references":4,"next":{"headline":"Mongoose: Path traversal in SSI #include directives enables arbitrary file read","id":"CVE-2026-73255"},"packages":[],"prev":{"headline":"Mongoose: TLS Hostname Verification Bypass via Overly Permissive Wildcard Matching","id":"CVE-2026-73253"},"products":["mongoose"],"published":"2026-08-20","related":[{"cvss_score":9.8,"headline":"Arbitrary File Write","id":"CVE-2022-25299","kev_date_added":null,"published":"2022-02-18"},{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2020-25756","kev_date_added":null,"published":"2020-09-18"},{"cvss_score":9.8,"headline":"Integer overflow in n/a","id":"CVE-2019-19307","kev_date_added":null,"published":"2019-11-26"},{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2019-12951","kev_date_added":null,"published":"2019-06-24"},{"cvss_score":9.8,"headline":"Use after free in n/a","id":"CVE-2018-20353","kev_date_added":null,"published":"2019-06-10"},{"cvss_score":9.8,"headline":"Use after free in n/a","id":"CVE-2018-20354","kev_date_added":null,"published":"2019-06-10"},{"cvss_score":9.8,"headline":"Use after free in n/a","id":"CVE-2018-20355","kev_date_added":null,"published":"2019-06-10"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"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":"2026-08-21","vendors":["cesanta"]},"summary":"Attackers can inject scripts via filenames in directory listings, allowing session theft or victim actions in Mongoose web servers.","url":"https://insights.sbomify.com/CVE-2026-73254/"}