{"answers":{"affected":"1 open source package ship an affected version, including mastodon.","exploited":"There is no known exploitation of CVE-2026-50128 in the wild and no public exploit code.","fix":"Upgrade mastodon to a fixed version for your release line: 4.4.18 or 4.5.11.","what":"CVE-2026-50128 is a medium-severity vulnerability in mastodon, published on 24 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-50128 and fix it if it is affected.\n\nWhat it is: CVE-2026-50128 is a medium-severity vulnerability in mastodon, published on 24 Jun 2026. 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-2026-50128 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- mastodon (Bitnami): affected from 4.3.0; fixed in 4.4.18, 4.5.11\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-2026-50128/ (Markdown: https://insights.sbomify.com/CVE-2026-50128/index.md)","id":"CVE-2026-50128","markdown":"https://insights.sbomify.com/CVE-2026-50128/index.md","name":"CVE-2026-50128","record":{"aliases":["BIT-mastodon-2026-50128"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"Mastodon social network","requires_auth":"none","summary":"Attackers can bypass signature verification to spoof author attribution domains in Mastodon social network posts.","user_interaction":"not_required","vuln_class":"security_feature_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":5.3,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-354","name":"Improper Validation of Integrity Check Value"}],"description":"Mastodon is a free, open-source social network server based on ActivityPub. From 4.3.0 until 4.5.11 and 4.4.18, Mastodon has a feature to let websites credit authors of their articles. To prevent false attribution claims, Mastodon uses the attributionDomains JSON-LD term, however, an error in how it is defined makes Linked Data Signatures on the toot:attributionDomains property ineffective. An attacker can arbitrarily modify the attributionDomains value of a legitimately signed Update activity and bypass Mastodon’s signature verification. This vulnerability is fixed in 4.5.11 and 4.4.18.","ecosystems":["Bitnami"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Mastodon: Spoofing of attribution domains","id":"CVE-2026-50128","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Bitnami","product":null,"products":[],"type":"security_feature_bypass","year":"2026"},"n_packages":1,"n_references":1,"next":{"headline":"Mastodon: Persistent anonymous DoS via unhandled NoMethodError in MATH_TRANSFORMER","id":"CVE-2026-50129"},"packages":[{"ecosystem":"Bitnami","fixed":["4.4.18","4.5.11"],"introduced":["4.3.0","4.5.0"],"last_affected":[],"package":"mastodon","purl":"pkg:bitnami/mastodon","source":"BIT-mastodon-2026-50128"}],"prev":{"headline":"Weblate SSRF: outbound URL guard misses the NAT64 well-known prefix (64:ff9b::/96)","id":"CVE-2026-50127"},"products":["mastodon"],"published":"2026-06-24","related":[],"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":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-06-25","vendors":["mastodon"]},"summary":"Attackers can bypass signature verification to spoof author attribution domains in Mastodon social network posts.","url":"https://insights.sbomify.com/CVE-2026-50128/"}