{"answers":{"affected":"It affects 1 product.","exploited":"Yes. Attackers have exploited CVE-2021-27137 in the wild since at least 21 Jul 2026.","fix":"No fix has been published for CVE-2021-27137 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 24 Jul 2026.","what":"CVE-2021-27137 is a high-severity memory corruption vulnerability in DD-WRT, published on 16 Jul 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-2021-27137 and fix it if it is affected.\n\nWhat it is: CVE-2021-27137 is a high-severity memory corruption vulnerability in DD-WRT, published on 16 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: Yes. Attackers have exploited CVE-2021-27137 in the wild since at least 21 Jul 2026.\n\nAffected product: DD-WRT. 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-2021-27137/ (Markdown: https://insights.sbomify.com/CVE-2021-27137/index.md)","id":"CVE-2021-27137","markdown":"https://insights.sbomify.com/CVE-2021-27137/index.md","name":"CVE-2021-27137","record":{"aliases":["GHSA-qx3v-2jx6-8m2c"],"analysis":{"component_type":"network_device","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":true,"product_category":"DD-WRT router firmware","requires_auth":"none","summary":"An unauthenticated remote attacker can execute arbitrary code via a buffer overflow in UPnP handling if UPnP is enabled.","user_interaction":"not_required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mitre","cpe":[{"product":"dd-wrt","vendor":"dd-wrt"}],"cvss":{"score":8.1,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-121","name":"Stack-based Buffer Overflow"}],"description":"An issue was discovered in router/upnp/src/ssdp.c in DD-WRT before 45724. An unsafe strcpy in the UPnP handling functionality allows an unauthenticated remote attacker to send a request that would overflow an internal fixed buffer. Exploitation requires the DD-WRT user to enable UPnP (which is off by default, and only listens on internal interfaces by default). This occurs in ssdp_msearch (reachable by an M-SEARCH request).","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"exploited"},"has_fix":null,"headline":"DD-WRT Stack-Based Buffer Overflow","id":"CVE-2021-27137","indexable":true,"kev":{"dateAdded":"2026-07-21","dueDate":"2026-07-24","knownRansomwareCampaignUse":"Unknown","product":"DD-WRT","requiredAction":"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.","vendorProject":"DD-WRT","vulnerabilityName":"DD-WRT Stack-Based Buffer Overflow Vulnerability"},"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"memory_corruption","year":"2021"},"n_packages":0,"n_references":5,"next":{"headline":"Other in n/a","id":"CVE-2021-27138"},"packages":[],"prev":{"headline":"Memory corruption in n/a","id":"CVE-2021-27135"},"products":["DD-WRT"],"published":"2026-07-16","related":[{"cvss_score":8.8,"headline":"Command injection in n/a","id":"CVE-2020-13976","kev_date_added":null,"published":"2020-06-09"},{"cvss_score":8.8,"headline":"Command injection in n/a","id":"CVE-2012-6297","kev_date_added":null,"published":"2020-02-06"},{"cvss_score":8.3,"headline":"Command injection in n/a","id":"CVE-2009-2765","kev_date_added":null,"published":"2009-08-14"},{"cvss_score":7.5,"headline":"Missing authorization in n/a","id":"CVE-2009-2766","kev_date_added":null,"published":"2009-08-14"},{"cvss_score":6.8,"headline":"Cross-site request forgery in n/a","id":"CVE-2008-6974","kev_date_added":null,"published":"2009-08-14"},{"cvss_score":6.8,"headline":"Cross-site request forgery in n/a","id":"CVE-2008-6975","kev_date_added":null,"published":"2009-08-14"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"open","licence":"CC0 1.0","name":"CISA KEV"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"active","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-07-22","vendors":["DD-WRT"]},"summary":"An unauthenticated remote attacker can execute arbitrary code via a buffer overflow in UPnP handling if UPnP is enabled.","url":"https://insights.sbomify.com/CVE-2021-27137/"}