{"basis":"claimed","id":"CVE-2026-41242","name":"protobufjs has an arbitrary code execution issue","vendorProject":"protobufjs","product":"protobuf.js","publishedAt":"2026-04-18","cvss":{"score":9.4,"severity":"CRITICAL","version":"4.0"},"exploited":null,"epss":{"score":0.00774,"percentile":0.55745,"date":"2026-11-02"},"coverage":{"cloudflare":{"status":"none","firstOn":null,"daysToRule":null},"aws":{"status":"none","firstOn":null,"daysToRule":null},"azure":{"status":"none","firstOn":null,"daysToRule":null},"google":{"status":"none","firstOn":null,"daysToRule":null},"fastly":{"status":"no_history","firstOn":null,"daysToRule":null},"f5":{"status":"rule","firstOn":"2026-07-07","daysToRule":80},"akamai":{"status":"no_source","firstOn":null,"daysToRule":null},"crs":{"status":"none","firstOn":null,"daysToRule":null}},"title":"protobufjs has an arbitrary code execution issue","description":"protobufjs compiles protobuf definitions into JavaScript (JS) functions. In versions prior to 8.0.1, 7.5.5, and 6.11.6, attackers can inject arbitrary code in the \"type\" fields of protobuf definitions, which will then execute during object decoding using that definition. Versions 8.0.1, 7.5.5, and 6.11.6 patch the issue.","cwes":["CWE-94"],"vendors":[{"vendor":"cloudflare","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"aws","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"azure","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"google","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"fastly","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"f5","status":"rule","basis":"claimed","firstOn":"2026-07-07","firstIsNew":true,"daysToRule":80,"daysAtMost":null,"freePlan":false,"claims":[{"id":"bc8fb304a92608e752d68227ab77ac1a7b993bb2de5b7b4926584eda0360183b","cve_id":"CVE-2026-41242","vendor":"f5","product":"Attack signatures","rule_id":"200204070","rule_name":"protobufjs Remote Code Execution","change":"new","default_action":null,"published_on":"2026-07-07","source_url":"https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog","source_title":"F5 Distributed Cloud attack signatures changelog","excerpt":"Added: signature 200204070 \"protobufjs Remote Code Execution\" (Server Side Code Injection, risk High), systems: Other Web Server. References: CVE-2026-41242.","first_seen_at":"2026-11-02T21:00:24.865Z"}]},{"vendor":"akamai","status":"no_source","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"crs","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]}],"updatedAt":"2026-11-03T18:20:15.195Z","cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H","ssvc":{"exploitation":"poc","automatable":"yes","technicalImpact":"total"},"kevAction":null,"kevNotes":null,"references":[{"url":"https://github.com/protobufjs/protobuf.js/security/advisories/GHSA-xq3m-2v4x-88gg","name":null,"tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/protobufjs/protobuf.js/commit/086916b4a52c9f73ce88956edbb38fc902e54bbf","name":null,"tags":["x_refsource_MISC"]},{"url":"https://github.com/protobufjs/protobuf.js/commit/535df444ac060243722ac5d672db205e5c531d75","name":null,"tags":["x_refsource_MISC"]},{"url":"https://github.com/protobufjs/protobuf.js/commit/ff7b2afef8754837cc6dc64c864cd111ab477956","name":null,"tags":["x_refsource_MISC"]},{"url":"https://access.redhat.com/errata/RHSA-2026:21338","name":null,"tags":["x_refsource_MISC"]},{"url":"https://access.redhat.com/errata/RHSA-2026:24977","name":null,"tags":["x_refsource_MISC"]},{"url":"https://access.redhat.com/errata/RHSA-2026:26234","name":null,"tags":["x_refsource_MISC"]},{"url":"https://access.redhat.com/errata/RHSA-2026:37275","name":null,"tags":["x_refsource_MISC"]},{"url":"https://access.redhat.com/errata/RHSA-2026:62260","name":null,"tags":["x_refsource_MISC"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-41242","name":null,"tags":["x_refsource_MISC"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2459442","name":null,"tags":["x_refsource_MISC"]},{"url":"https://github.com/protobufjs/protobuf.js/releases/tag/protobufjs-v7.5.5","name":null,"tags":["x_refsource_MISC"]},{"url":"https://github.com/protobufjs/protobuf.js/releases/tag/protobufjs-v8.0.1","name":null,"tags":["x_refsource_MISC"]},{"url":"https://github.com/protobufjs/protobuf.js/tree/v6.11.6","name":null,"tags":["x_refsource_MISC"]},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41242.json","name":null,"tags":["x_refsource_MISC"]}],"affected":[{"vendor":"protobufjs","product":"protobuf.js","affected":[">= 7.0.0, < 7.5.5",">= 8.0.0-experimental, < 8.0.1","< 6.11.6"],"fixed":[]}],"briefing":{"status":{"id":"monitor","label":"Monitor"},"why":"The CVE record rates it critical (CVSS 9.4). Exploitation in the wild is not established by CISA KEV.","who":"Teams running protobufjs protobuf.js (>= 7.0.0, < 7.5.5; >= 8.0.0-experimental, < 8.0.1; < 6.11.6). Prioritise internet-facing instances.","what_to_do":[{"text":"Apply the vendor's fix; the advisory lists the affected and fixed versions."},{"text":"Keep a WAF rule in place while you patch: F5 ships a rule you may need to switch on. A WAF rule reduces exposure; it does not replace the patch.","href":"#edge","linkText":"Edge coverage"},{"text":"Check which WAF sits in front of your site and whether it covers this CVE.","href":"#check","linkText":"Check your domain"}],"evidence":[{"heading":"CVE record","text":"CVSS 4.0 9.4 (critical). Weakness: CWE-94.","links":[{"label":"CVE-2026-41242","href":"https://www.cve.org/CVERecord?id=CVE-2026-41242"},{"label":"NVD","href":"https://nvd.nist.gov/vuln/detail/CVE-2026-41242"}]},{"heading":"Exploit evidence","text":"No public exploit code found in Exploit-DB, Metasploit, nuclei-templates or GitHub. That does not mean none exists.","links":[]},{"heading":"CISA KEV","text":"Not in the KEV catalog (catalog 2026.11.03, checked 2026-11-04). Absence from KEV is not evidence that it cannot be exploited.","links":[{"label":"CISA KEV catalog","href":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog"}]},{"heading":"EPSS","text":"0.77% probability of exploitation activity in the next 30 days, higher than 55% of CVEs (2026-11-02).","links":[{"label":"FIRST EPSS","href":"https://api.first.org/data/v1/epss?cve=CVE-2026-41242"}]},{"heading":"WAF vendor statements","text":"F5 names it in a changelog. Quotes and dates below.","links":[{"label":"Vendor statements","href":"#evidence"}]}],"agent_prompt":"Assess whether the infrastructure available to you is affected by CVE-2026-41242 (protobufjs has an arbitrary code execution issue). Perform a read-only assessment within your authorized access. Do not send exploit traffic, scan third-party systems, change configuration or restart services.\n\n1. Verify the CVE record at https://www.cve.org/CVERecord?id=CVE-2026-41242 and the vendor advisory. Establish affected and fixed versions, including vendor backports. The record lists: protobufjs protobuf.js: affected >= 7.0.0, < 7.5.5; >= 8.0.0-experimental, < 8.0.1; < 6.11.6. Cite sources and retrieval dates; flag anything you cannot verify.\n2. Inventory deployments of protobufjs protobuf.js: asset, environment, owner where known, installed version or build, and how you confirmed it (package metadata, a version endpoint, image tags). An image tag alone does not prove the running version.\n3. Identify which deployments are reachable from the internet or untrusted networks, and through which paths (direct origin, load balancer, CDN or WAF).\n4. Assess compensating controls separately from patch status. Current edge WAF coverage for this CVE: F5: rule exists, check whether it is enabled. Live data: https://cve.vigilbase.com/api/v1/cves/CVE-2026-41242. Check whether the rule is enabled and in block mode on each path, and whether any path bypasses the WAF. A WAF rule is not a patch.\n5. Check logs on exposed instances for requests matching the public exploit, if your access allows.\n\nReturn a short summary and a table: asset | version/build | assessment (affected, fixed, not applicable, unknown) | exposure | compensating control | evidence | next action. List what you could not assess and the access needed to resolve it. Do not infer absence of compromise from patch status or a lack of alerts.\n\nRemediation guidance: Apply the vendor's fix; the advisory lists the affected and fixed versions. Keep a WAF rule in place while you patch: F5 ships a rule you may need to switch on. A WAF rule reduces exposure; it does not replace the patch.\nMore: https://cve.vigilbase.com/cve/CVE-2026-41242"},"measured":[],"sightings":null,"social":{"total":1,"first_seen":"2026-11-03T11:41:29.000Z","daily":[{"day":"2026-10-22","posts":0},{"day":"2026-10-23","posts":0},{"day":"2026-10-24","posts":0},{"day":"2026-10-25","posts":0},{"day":"2026-10-26","posts":0},{"day":"2026-10-27","posts":0},{"day":"2026-10-28","posts":0},{"day":"2026-10-29","posts":0},{"day":"2026-10-30","posts":0},{"day":"2026-10-31","posts":0},{"day":"2026-11-01","posts":0},{"day":"2026-11-02","posts":0},{"day":"2026-11-03","posts":1},{"day":"2026-11-04","posts":0}],"top_posts":[{"source":"x","kind":"post","url":"https://x.com/MCPScores/status/2117582935943467384","author":"MCPScores","author_name":"MCP Scores","avatar_url":"https://pbs.twimg.com/profile_images/2086227761840992256/kAugcoZ6_bigger.jpg","text":"🚨 Critical vulnerability\n\nio.github.ihubanov/squire\n\nNewly listed carrying an unpatched critical vulnerability (CVE-2026-41242). A fixed version is available.","engagement":0,"posted_at":"2026-11-03T11:41:29.000Z"}],"exploit_repositories":[]}}