{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-39220 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2021-39220 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-39220 is a low-severity vulnerability in nextcloud security-advisories, published on 25 Oct 2021. 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-2021-39220 and fix it if it is affected.\n\nWhat it is: CVE-2021-39220 is a low-severity vulnerability in nextcloud security-advisories, published on 25 Oct 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2021-39220 in the wild and no public exploit code.\n\nAffected product: nextcloud security-advisories. 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-2021-39220/ (Markdown: https://insights.sbomify.com/CVE-2021-39220/index.md)","id":"CVE-2021-39220","markdown":"https://insights.sbomify.com/CVE-2021-39220/index.md","name":"CVE-2021-39220","record":{"aliases":["GHSA-6q9v-wm8r-rcv5"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["data_read"],"network_reachable":"yes","non_default_config":false,"product_category":"Nextcloud Mail app","requires_auth":"low_privilege","summary":"Attackers can bypass image blocking in Nextcloud Mail to leak user IP addresses and read state via relative protocol images.","user_interaction":"required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"mail","vendor":"nextcloud"}],"cvss":{"score":3.5,"severity":"low","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-200","name":"Exposure of Sensitive Information to an Unauthorized Actor"},{"id":"CWE-20","name":"Improper Input Validation"}],"description":"Nextcloud is an open-source, self-hosted productivity platform The Nextcloud Mail application prior to versions 1.10.4 and 1.11.0 does by default not render images in emails to not leak the read state or user IP. The privacy filter failed to filter images with a relative protocol. It is recommended that the Nextcloud Mail application is upgraded to 1.10.4 or 1.11.0. There are no known workarounds aside from upgrading.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"Bypass of image blocking in Nextcloud Mail","id":"CVE-2021-39220","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"information_disclosure","year":"2021"},"n_packages":0,"n_references":3,"next":{"headline":"XSS in Contacts","id":"CVE-2021-39221"},"packages":[],"prev":{"headline":"Wrong type for `Linker`-define functions when used across two `Engine`s","id":"CVE-2021-39219"},"products":["security-advisories"],"published":"2021-10-25","related":[{"cvss_score":8.8,"headline":"Missing permission check on email metadata retrieval","id":"CVE-2021-32652","kev_date_added":null,"published":"2021-06-01"},{"cvss_score":8.3,"headline":"Unauthenticated SSRF in 3rd party module \"cerdic/csstidy\"","id":"CVE-2022-31132","kev_date_added":null,"published":"2022-08-04"},{"cvss_score":8.2,"headline":"Nextcloud Mail auto configurator can be tricked into sending account information to wrong servers","id":"CVE-2024-52508","kev_date_added":null,"published":"2024-11-15"},{"cvss_score":5,"headline":"Blind SSRF via server URL input in the Nextcloud Mail app","id":"CVE-2023-23943","kev_date_added":null,"published":"2023-02-06"},{"cvss_score":4.3,"headline":"Require strict cookies for image proxy requests in Nextcloud Mail","id":"CVE-2023-45660","kev_date_added":null,"published":"2023-10-16"},{"cvss_score":4.3,"headline":"Bypass of image blocking in Nextcloud Mail","id":"CVE-2021-32707","kev_date_added":null,"published":"2021-07-12"},{"cvss_score":4.1,"headline":"IDOR Vulnerability in Nextcloud Mail","id":"CVE-2023-25160","kev_date_added":null,"published":"2023-02-13"}],"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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-04","vendors":["nextcloud"]},"summary":"Attackers can bypass image blocking in Nextcloud Mail to leak user IP addresses and read state via relative protocol images.","url":"https://insights.sbomify.com/CVE-2021-39220/"}