{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-66912 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-66912 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-66912 is a medium-severity vulnerability in Synacor Zimbra Collaboration, published on 29 Oct 2026."},"fix_prompt":"Check this codebase for CVE-2026-66912 and fix it if it is affected.\n\nWhat it is: CVE-2026-66912 is a medium-severity vulnerability in Synacor Zimbra Collaboration, published on 29 Oct 2026. \nExploitation: There is no known exploitation of CVE-2026-66912 in the wild and no public exploit code.\n\nAffected product: Synacor Zimbra Collaboration. 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-2026-66912/ (Markdown: https://insights.sbomify.com/CVE-2026-66912/index.md)","id":"CVE-2026-66912","markdown":"https://insights.sbomify.com/CVE-2026-66912/index.md","name":"CVE-2026-66912","record":{"aliases":["GHSA-rprc-q5mj-4mcw"],"analysis":null,"analysis_generated_by":null,"assigner":"CERT-PL","cpe":[],"cvss":{"score":5.3,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/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":"Zimbra is vulnerable to Stored Cross-Site Scripting (XSS) via the From email header during HTML reply composition in Classic UI. Due to insufficient sanitization of the From header value, a remote attacker can send a crafted email containing a malicious From header with an embedded JavaScript payload. When the victim opens the message in Classic UI and clicks Reply while composing in HTML mode with reply headers disabled, the unsanitized From header content is rendered as HTML and the JavaScript payload executes in the victim's browser, potentially allowing the attacker to steal session information or perform actions on behalf of the victim. This issue was fixed in version 10.1.21","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":null,"headline":"Stored Cross-Site Scripting in Zimbra","id":"CVE-2026-66912","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":null,"year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"Zip Bomb in Lookyloo Capture Upload Allows Denial of Service","id":"CVE-2026-66913"},"packages":[],"prev":{"headline":"Stored Cross-Site Scripting in Zimbra","id":"CVE-2026-66911"},"products":["Zimbra Collaboration"],"published":"2026-10-29","related":[],"sources":[{"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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-29","vendors":["Synacor"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2026-66912/"}