{"answers":{"affected":"10 open source packages ship an affected version, including phpoffice/phpspreadsheet. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-35453 exists.","fix":"Upgrade phpoffice/phpspreadsheet to a fixed version for your release line: 1.30.4, 2.1.16, 2.4.5 or 3.10.5.","what":"CVE-2026-35453 is a medium-severity cross-site scripting vulnerability in PHPOffice PhpSpreadsheet, published on 5 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-35453 and fix it if it is affected.\n\nWhat it is: CVE-2026-35453 is a medium-severity cross-site scripting vulnerability in PHPOffice PhpSpreadsheet, published on 5 May 2026. Any signed-in user can exploit it over the network, 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-2026-35453 exists.\n\nAffected packages and fixed versions:\n- phpoffice/phpspreadsheet (Packagist): affected all versions; fixed in 1.30.4\n- phpoffice/phpspreadsheet (Packagist): affected all versions; fixed in 1.30.4\n- phpoffice/phpspreadsheet (Packagist): affected from 2.0.0; fixed in 2.1.16\n- phpoffice/phpspreadsheet (Packagist): affected from 2.0.0; fixed in 2.1.16\n- phpoffice/phpspreadsheet (Packagist): affected from 2.2.0; fixed in 2.4.5\n- phpoffice/phpspreadsheet (Packagist): affected from 2.2.0; fixed in 2.4.5\n- phpoffice/phpspreadsheet (Packagist): affected from 3.3.0; fixed in 3.10.5\n- phpoffice/phpspreadsheet (Packagist): affected from 3.3.0; fixed in 3.10.5\n- phpoffice/phpspreadsheet (Packagist): affected from 4.0.0; fixed in 5.7.0\n- phpoffice/phpspreadsheet (Packagist): affected from 4.0.0; fixed in 5.7.0\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-2026-35453/ (Markdown: https://insights.sbomify.com/CVE-2026-35453/index.md)","id":"CVE-2026-35453","markdown":"https://insights.sbomify.com/CVE-2026-35453/index.md","name":"CVE-2026-35453","record":{"aliases":["GHSA-6wpp-88cp-7q68"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"PHP spreadsheet library","requires_auth":"low_privilege","summary":"Attackers can inject arbitrary HTML and JavaScript into spreadsheet outputs via the HTML Writer, potentially leading to code execution in consuming applications.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"phpspreadsheet","vendor":"phpoffice"}],"cvss":{"score":4.8,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","version":"4.0"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"}],"description":"PhpSpreadsheet is a library for reading and writing spreadsheet files. In versions 1.30.3 and earlier, 2.0.0 through 2.1.15, 2.2.0 through 2.4.4, 3.3.0 through 3.10.4, and 4.0.0 through 5.6.0, the HTML Writer skips htmlspecialchars() output escaping when a cell uses a custom number format containing the @ text placeholder with additional literal text (e.g., @ \"items\"). The escaping is only applied when the formatted output strictly equals the original cell value. When the format code contains @ with quoted literal text, the formatter substitutes the raw cell value into the format string and returns early without invoking the escaping callback. An attacker who can control cell content in a spreadsheet processed by the HTML Writer can inject arbitrary HTML and JavaScript into the generated output. This issue has been fixed in versions 1.30.4, 2.1.16, 2.4.5, 3.10.5, and 5.7.0.","ecosystems":["Packagist"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"PhpSpreadsheet XSS via number format text substitution in HTML Writer","id":"CVE-2026-35453","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Packagist","product":null,"products":[],"type":"xss","year":"2026"},"n_packages":10,"n_references":1,"next":{"headline":"Code Extension Marketplace has a Zip Slip Path Traversal","id":"CVE-2026-35454"},"packages":[{"ecosystem":"Packagist","fixed":["1.30.4"],"introduced":["0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":null,"source":"GHSA-6wpp-88cp-7q68"},{"ecosystem":"Packagist","fixed":["1.30.4"],"introduced":["0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":"pkg:composer/phpoffice/phpspreadsheet","source":"GHSA-6wpp-88cp-7q68"},{"ecosystem":"Packagist","fixed":["2.1.16"],"introduced":["2.0.0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":null,"source":"GHSA-6wpp-88cp-7q68"},{"ecosystem":"Packagist","fixed":["2.1.16"],"introduced":["2.0.0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":"pkg:composer/phpoffice/phpspreadsheet","source":"GHSA-6wpp-88cp-7q68"},{"ecosystem":"Packagist","fixed":["2.4.5"],"introduced":["2.2.0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":null,"source":"GHSA-6wpp-88cp-7q68"},{"ecosystem":"Packagist","fixed":["2.4.5"],"introduced":["2.2.0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":"pkg:composer/phpoffice/phpspreadsheet","source":"GHSA-6wpp-88cp-7q68"},{"ecosystem":"Packagist","fixed":["3.10.5"],"introduced":["3.3.0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":null,"source":"GHSA-6wpp-88cp-7q68"},{"ecosystem":"Packagist","fixed":["3.10.5"],"introduced":["3.3.0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":"pkg:composer/phpoffice/phpspreadsheet","source":"GHSA-6wpp-88cp-7q68"},{"ecosystem":"Packagist","fixed":["5.7.0"],"introduced":["4.0.0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":null,"source":"GHSA-6wpp-88cp-7q68"},{"ecosystem":"Packagist","fixed":["5.7.0"],"introduced":["4.0.0"],"last_affected":[],"package":"phpoffice/phpspreadsheet","purl":"pkg:composer/phpoffice/phpspreadsheet","source":"GHSA-6wpp-88cp-7q68"}],"prev":{"headline":"WWBN AVideo has Unauthenticated Information Disclosure via Missing Auth on CloneSite client.log.php","id":"CVE-2026-35452"},"products":["PhpSpreadsheet"],"published":"2026-05-05","related":[{"cvss_score":9.2,"headline":"PhpSpreadsheet SSRF and RCE via PHP stream wrappers in IOFactory::load","id":"CVE-2026-34084","kev_date_added":null,"published":"2026-05-05"},{"cvss_score":8.8,"headline":"XML External Entity Reference (XXE) in PHPSpreadsheet","id":"CVE-2024-45048","kev_date_added":null,"published":"2024-08-28"},{"cvss_score":8.8,"headline":"XXE in PHPSpreadsheet due to incomplete fix for previous encoding issue","id":"CVE-2019-12331","kev_date_added":null,"published":"2019-11-07"},{"cvss_score":8.8,"headline":"XXE in PHPSpreadsheet due to encoding issue","id":"CVE-2018-19277","kev_date_added":null,"published":"2018-11-14"},{"cvss_score":8.3,"headline":"PhpSpreadsheet vulnerable to unauthorized reflected XSS in the constructor of the Downloader class","id":"CVE-2024-56365","kev_date_added":null,"published":"2025-01-03"},{"cvss_score":8.3,"headline":"PhpSpreadsheet vulnerable to unauthorized reflected XSS in the Accounting.php file","id":"CVE-2024-56366","kev_date_added":null,"published":"2025-01-03"},{"cvss_score":8.3,"headline":"PhpSpreadsheet allows unauthorized reflected XSS in `Convert-Online.php` file","id":"CVE-2024-56408","kev_date_added":null,"published":"2025-01-03"}],"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":"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":"2026-05-06","vendors":["PHPOffice"]},"summary":"Attackers can inject arbitrary HTML and JavaScript into spreadsheet outputs via the HTML Writer, potentially leading to code execution in consuming applications.","url":"https://insights.sbomify.com/CVE-2026-35453/"}