{"schema":"threatline.record/2","record":{"id":"CVE-2021-27137","aliases":[],"summary":"DD-WRT Stack-Based Buffer Overflow Vulnerability","details":"DD-WRT contains a stack-based buffer overflow vulnerability that could allow an unauthenticated attacker to overflow an internal buffer used by UPnP and trigger a code execution vulnerability.","categories":["Unclassified"],"product":"DD-WRT","vendor":"DD-WRT","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2021-27137","source_modified_at":"2026-07-22T03:55:45.793Z","fetched_at":"2026-10-23T18:42:43.628194Z","product":"DD-WRT","vendor":"DD-WRT","versions":[{"lessThan":"45724","status":"affected","version":"0","versionType":"custom"}],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2021-27137","source_modified_at":"2026-07-22T03:55:45.793Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"name":"DD-WRT","ecosystem":null},"version":"45724","basis":"first unaffected version stated in the CVE record"}],"cvss":8.1,"severity":"High","kev":{"listed":true,"date_added":"2026-07-21","due_date":"2026-07-24","required_action":"Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.","ransomware_campaign_use":"Unknown","forensic_triage":true},"epss":{"probability":0.03995,"percentile":0.90481,"score_date":"2026-10-23"},"published_at":"2026-07-16T00:00:00.000Z","modified_at":"2026-07-22T03:55:45.793Z","provenance":[{"source":"CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23T17:00:09.9001Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2021-27137","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-07-22T03:55:45.793Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2021-27137","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CISA KEV","CVE List","EPSS"],"references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-27137","source":"CISA KEV"},{"source":"CVE List","url":"https://svn.dd-wrt.com/changeset/45724"},{"source":"CVE List","url":"https://ssd-disclosure.com/ssd-advisory-dd-wrt-upnp-buffer-overflow/","tags":["exploit"]},{"source":"CVE List","url":"https://securityaffairs.com/193290/uncategorized/iot-botnet-c0xmo-adds-competitor-killing-capability.html"},{"source":"CVE List","url":"https://www.bleepingcomputer.com/news/security/c0xmo-botnet-spreads-via-dd-wrt-router-flaw-kills-rival-malware/"},{"source":"CVE List","url":"https://www.fortinet.com/blog/threat-research/inside-cross-platform-propagation-of-new-gafgyt-variant-c0xmo"},{"source":"CVE List","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27137","tags":["government-resource"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"active","automatable":"no","technical_impact":"total","assessed_at":"2026-07-21T00:00:00+00:00"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-07-22T03:55:45.793Z","content_hash":"ab5c65d6ccf48ce990f2712fbff5988a342cab1e887832ea2a40518f8a06a0c7"}}