{"answers":{"affected":"It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42376 exists.","fix":"No fix has been published for CVE-2026-42376 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-42376 is a critical vulnerability in D-Link DIR-456U Firmware, published on 4 May 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-2026-42376 and fix it if it is affected.\n\nWhat it is: CVE-2026-42376 is a critical vulnerability in D-Link DIR-456U Firmware, published on 4 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42376 exists.\n\nAffected product: D-Link DIR-456U Firmware. 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-2026-42376/ (Markdown: https://insights.sbomify.com/CVE-2026-42376/index.md)","id":"CVE-2026-42376","markdown":"https://insights.sbomify.com/CVE-2026-42376/index.md","name":"CVE-2026-42376","record":{"aliases":["GHSA-8fmw-7p6g-ww4q"],"analysis":{"component_type":"iot_embedded","fix_type":"end_of_life","impacts":["code_execution","privilege_escalation"],"network_reachable":"yes","non_default_config":false,"product_category":"D-Link router firmware","requires_auth":"none","summary":"Attackers on the local network can use hardcoded credentials to gain root access to the EOL D-Link DIR-456U router.","user_interaction":"not_required","vuln_class":"hardcoded_credentials"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"securin","cpe":[{"product":"dir-456u_firmware","vendor":"dlink"}],"cvss":{"score":9.8,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-798","name":"Use of Hard-coded Credentials"}],"description":"D-Link DIR-456U Hardware Revision A1 (End-of-Life, EOL) contains a hardcoded telnet backdoor. The device starts a telnet daemon at boot via /etc/init0.d/S80telnetd.sh with the username \"Alphanetworks\" and the static password \"whdrv01_dlob_dir456U\" read from /etc/config/image_sign. The custom telnetd binary accepts a -u user:password flag, and the custom login binary uses strcmp() to validate credentials. Successful authentication grants an unauthenticated attacker on the local network a root shell with full administrative control. The device has reached End-of-Life (EOL) and will not receive patches.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":null,"headline":"D-Link DIR-456U A1 Hardcoded Telnet Backdoor Credentials","id":"CVE-2026-42376","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"hardcoded_credentials","year":"2026"},"n_packages":0,"n_references":1,"next":{"headline":"WordPress SureForms Pro plugin \u003c= 2.8.0 - Broken Access Control vulnerability","id":"CVE-2026-42377"},"packages":[],"prev":{"headline":"D-Link DIR-600L A1 Hardcoded Telnet Backdoor Credentials","id":"CVE-2026-42375"},"products":["DIR-456U Firmware"],"published":"2026-05-04","related":[],"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":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-05-04","vendors":["D-Link"]},"summary":"Attackers on the local network can use hardcoded credentials to gain root access to the EOL D-Link DIR-456U router.","url":"https://insights.sbomify.com/CVE-2026-42376/"}