{"answers":{"affected":"2 open source packages ship an affected version, including next. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-27977 in the wild and no public exploit code.","fix":"Upgrade next to 16.1.7 or later.","what":"CVE-2026-27977 is a low-severity vulnerability in Vercel Next.js, published on 17 Mar 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-27977 and fix it if it is affected.\n\nWhat it is: CVE-2026-27977 is a low-severity vulnerability in Vercel Next.js, published on 17 Mar 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-27977 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- next (npm): affected from 16.0.1; fixed in 16.1.7\n- next (npm): affected from 16.0.1; fixed in 16.1.7\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-2026-27977/ (Markdown: https://insights.sbomify.com/CVE-2026-27977/index.md)","id":"CVE-2026-27977","markdown":"https://insights.sbomify.com/CVE-2026-27977/index.md","name":"CVE-2026-27977","record":{"aliases":["GHSA-jcc7-9wpm-mj36","MINI-2cf9-7cm4-pw78","MINI-cm4h-5qgp-wv26","ROOT-APP-NPM-CVE-2026-27977"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["security_bypass","data_read"],"network_reachable":"yes","non_default_config":false,"product_category":"Next.js framework","requires_auth":"none","summary":"Attackers can bypass CSRF protections in Next.js development mode via null origin, allowing unauthorized access to HMR websocket channels.","user_interaction":"required","vuln_class":"csrf"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"next.js","vendor":"vercel"}],"cvss":{"score":2.3,"severity":"low","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-1385","name":"Missing Origin Validation in WebSockets"}],"description":"Next.js is a React framework for building full-stack web applications. Starting in version 16.0.1 and prior to version 16.1.7, in `next dev`, cross-site protection for internal websocket endpoints could treat `Origin: null` as a bypass case even if `allowedDevOrigins` is configured, allowing privacy-sensitive/opaque contexts (for example sandboxed documents) to connect unexpectedly. If a dev server is reachable from attacker-controlled content, an attacker may be able to connect to the HMR websocket channel and interact with dev websocket traffic. This affects development mode only. Apps without a configured `allowedDevOrigins` still allow connections from any origin. The issue is fixed in version 16.1.7 by validating `Origin: null` through the same cross-site origin-allowance checks used for other origins. If upgrading is not immediately possible, do not expose `next dev` to untrusted networks and/or block websocket upgrades to `/_next/webpack-hmr` when `Origin` is `null` at the proxy.","ecosystems":["npm"],"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":"Next.js: null origin can bypass dev HMR websocket CSRF checks","id":"CVE-2026-27977","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":"vercel:next.js","products":["vercel:next.js"],"type":"csrf","year":"2026"},"n_packages":2,"n_references":3,"next":{"headline":"Next.js: null origin can bypass Server Actions CSRF checks","id":"CVE-2026-27978"},"packages":[{"ecosystem":"npm","fixed":["16.1.7"],"introduced":["16.0.1"],"last_affected":[],"package":"next","purl":null,"source":"GHSA-jcc7-9wpm-mj36"},{"ecosystem":"npm","fixed":["16.1.7"],"introduced":["16.0.1"],"last_affected":[],"package":"next","purl":"pkg:npm/next","source":"GHSA-jcc7-9wpm-mj36"}],"prev":{"headline":"Zed Extension Sandbox Escape via Tar Symlink Following","id":"CVE-2026-27976"},"products":["next.js"],"published":"2026-03-17","related":[{"cvss_score":9.1,"headline":"Authorization Bypass in Next.js Middleware","id":"CVE-2025-29927","kev_date_added":null,"published":"2025-03-21"},{"cvss_score":8.6,"headline":"Next.js: Server-side request forgery in applications using WebSocket upgrades","id":"CVE-2026-44578","kev_date_added":null,"published":"2026-05-13"},{"cvss_score":8.3,"headline":"Next.js: Server-Side Request Forgery in Image Optimization","id":"CVE-2026-94483","kev_date_added":null,"published":"2026-10-02"},{"cvss_score":8.3,"headline":"Next.js: Middleware / Proxy bypass in App Router applications using Turbopack and single locale","id":"CVE-2026-64642","kev_date_added":null,"published":"2026-07-27"},{"cvss_score":8.3,"headline":"Next.js: Server-Side Request Forgery in rewrites via attacker-controlled destination hostname","id":"CVE-2026-64645","kev_date_added":null,"published":"2026-07-27"},{"cvss_score":8.3,"headline":"Next.js: Server-Side Request Forgery in Server Actions on Custom Servers","id":"CVE-2026-64649","kev_date_added":null,"published":"2026-07-27"},{"cvss_score":8.2,"headline":"Next.js: Denial of Service in App Router using Server Actions","id":"CVE-2026-64641","kev_date_added":null,"published":"2026-07-27"}],"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":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-03-18","vendors":["vercel"]},"summary":"Attackers can bypass CSRF protections in Next.js development mode via null origin, allowing unauthorized access to HMR websocket channels.","url":"https://insights.sbomify.com/CVE-2026-27977/"}