{"answers":{"affected":"3 open source packages ship an affected version, including libphp, php and php-min. It affects 4 products.","exploited":"There is no known exploitation of CVE-2021-21707 in the wild and no public exploit code.","fix":"Upgrade libphp to a fixed version for your release line: 7.3.33, 7.4.26 or 8.0.13.","what":"CVE-2021-21707 is a medium-severity path traversal vulnerability in Debian Debian Linux, published on 29 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-21707 and fix it if it is affected.\n\nWhat it is: CVE-2021-21707 is a medium-severity path traversal vulnerability in Debian Debian Linux, published on 29 Nov 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-21707 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- libphp (Bitnami): affected from 7.3.0; fixed in 7.3.33, 7.4.26, 8.0.13\n- php (Bitnami): affected from 7.3.0; fixed in 7.3.33, 7.4.26, 8.0.13\n- php-min (Bitnami): affected from 7.3.0; fixed in 7.3.33, 7.4.26, 8.0.13\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-2021-21707/ (Markdown: https://insights.sbomify.com/CVE-2021-21707/index.md)","id":"CVE-2021-21707","markdown":"https://insights.sbomify.com/CVE-2021-21707/index.md","name":"CVE-2021-21707","record":{"aliases":["BIT-libphp-2021-21707","BIT-php-2021-21707","BIT-php-min-2021-21707","DEBIAN-CVE-2021-21707","ECHO-5db2-f6f6-1773","GHSA-qh78-qfw9-93x9","MGASA-2021-0519","OESA-2021-1455","SUSE-SU-2021:3927-1","UBUNTU-CVE-2021-21707","openSUSE-SU-2024:11638-1","openSUSE-SU-2024:11640-1"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["data_read"],"network_reachable":"yes","non_default_config":false,"product_category":"PHP XML parser","requires_auth":"none","summary":"Attackers can bypass filename restrictions in PHP XML functions by using URL-encoded NUL characters to read unintended files.","user_interaction":"not_required","vuln_class":"path_traversal"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"php","cpe":[{"product":"debian_linux","vendor":"debian"},{"product":"clustered_data_ontap","vendor":"netapp"},{"product":"php","vendor":"php"},{"product":"tenable.sc","vendor":"tenable"}],"cvss":{"score":5.3,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-159","name":"Improper Handling of Invalid Use of Special Elements"}],"description":"In PHP versions 7.3.x below 7.3.33, 7.4.x below 7.4.26 and 8.0.x below 8.0.13, certain XML parsing functions, like simplexml_load_file(), URL-decode the filename passed to them. If that filename contains URL-encoded NUL character, this may cause the function to interpret this as the end of the filename, thus interpreting the filename differently from what the user intended, which may lead it to reading a different file than intended.","ecosystems":["Bitnami","SUSE:Linux Enterprise Module for Web and Scripting 12","SUSE:Linux Enterprise Software Development Kit 12 SP5","openSUSE:Tumbleweed"],"exploits":{"exploitdb":0,"first_seen":"2025-09-08","github_poc":1,"max_poc_stars":0,"metasploit":0,"nuclei":0,"refs":[{"date":"2025-09-08T10:19:10Z","kind":"github_poc","ref":"https://github.com/useru1k/php-8.1.0-dev-exploit","stars":0,"title":"Exploit for the PHP 8.1.0-dev backdoor vulnerability (CVE-2021-21707)"}],"tier":"poc_unverified"},"has_fix":true,"headline":"Special characters break path parsing in XML functions","id":"CVE-2021-21707","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Bitnami","product":"debian:debian_linux","products":["debian:debian_linux","netapp:clustered_data_ontap","php:php"],"type":"path_traversal","year":"2021"},"n_packages":7,"n_references":5,"next":{"headline":"UAF due to php_filter_float() failing","id":"CVE-2021-21708"},"packages":[{"ecosystem":"Bitnami","fixed":["7.3.33","7.4.26","8.0.13"],"introduced":["7.3.0","7.4.0","8.0.0"],"last_affected":[],"package":"libphp","purl":"pkg:bitnami/libphp","source":"BIT-libphp-2021-21707"},{"ecosystem":"Bitnami","fixed":["7.3.33","7.4.26","8.0.13"],"introduced":["7.3.0","7.4.0","8.0.0"],"last_affected":[],"package":"php","purl":"pkg:bitnami/php","source":"BIT-php-2021-21707"},{"ecosystem":"Bitnami","fixed":["7.3.33","7.4.26","8.0.13"],"introduced":["7.3.0","7.4.0","8.0.0"],"last_affected":[],"package":"php-min","purl":"pkg:bitnami/php-min","source":"BIT-php-min-2021-21707"},{"ecosystem":"SUSE:Linux Enterprise Module for Web and Scripting 12","fixed":["7.4.6-1.30.1"],"introduced":["0"],"last_affected":[],"package":"php74","purl":"pkg:rpm/suse/php74\u0026distro=SUSE%20Linux%20Enterprise%20Module%20for%20Web%20and%20Scripting%2012","source":"SUSE-SU-2021:3927-1"},{"ecosystem":"SUSE:Linux Enterprise Software Development Kit 12 SP5","fixed":["7.4.6-1.30.1"],"introduced":["0"],"last_affected":[],"package":"php74","purl":"pkg:rpm/suse/php74\u0026distro=SUSE%20Linux%20Enterprise%20Software%20Development%20Kit%2012%20SP5","source":"SUSE-SU-2021:3927-1"},{"ecosystem":"openSUSE:Tumbleweed","fixed":["7.4.26-1.1"],"introduced":["0"],"last_affected":[],"package":"php7","purl":"pkg:rpm/opensuse/php7\u0026distro=openSUSE%20Tumbleweed","source":"openSUSE-SU-2024:11640-1"},{"ecosystem":"openSUSE:Tumbleweed","fixed":["8.0.13-1.1"],"introduced":["0"],"last_affected":[],"package":"php8","purl":"pkg:rpm/opensuse/php8\u0026distro=openSUSE%20Tumbleweed","source":"openSUSE-SU-2024:11638-1"}],"prev":{"headline":"ZipArchive::extractTo may extract outside of destination dir","id":"CVE-2021-21706"},"products":["PHP"],"published":"2021-11-29","related":[{"cvss_score":10,"headline":"ProFTPD Improper Access Control","id":"CVE-2015-3306","kev_date_added":"2026-10-08","published":"2015-05-18"},{"cvss_score":9.9,"headline":"RoundCube Webmail Deserialization of Untrusted Data","id":"CVE-2025-49113","kev_date_added":"2026-02-20","published":"2025-06-02"},{"cvss_score":9.8,"headline":"GNU InetUtils Argument Injection","id":"CVE-2026-24061","kev_date_added":"2026-01-26","published":"2026-01-21"},{"cvss_score":9.8,"headline":"Linux Kernel Improper Check for Unusual or Exceptional Conditions","id":"CVE-2025-39682","kev_date_added":"2026-09-18","published":"2025-09-05"},{"cvss_score":9.8,"headline":"Mozilla Firefox Use-After-Free","id":"CVE-2024-9680","kev_date_added":"2024-10-15","published":"2024-10-09"},{"cvss_score":9.8,"headline":"RARLAB UnRAR Directory Traversal","id":"CVE-2022-30333","kev_date_added":"2022-08-09","published":"2022-05-09"},{"cvss_score":9.8,"headline":"Roundcube Webmail SQL Injection","id":"CVE-2021-44026","kev_date_added":"2023-06-22","published":"2021-11-19"}],"sources":[{"class":"attribution","licence":"Apache-2.0","name":"Bitnami","prefix":"BIT"},{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"SUSE","prefix":"SUSE"},{"class":"attribution","licence":"CC BY 4.0","name":"SUSE","prefix":"openSUSE"},{"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)"},{"class":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-09-17","vendors":["PHP Group"]},"summary":"Attackers can bypass filename restrictions in PHP XML functions by using URL-encoded NUL characters to read unintended files.","url":"https://insights.sbomify.com/CVE-2021-21707/"}