{"dataType": "CVE_RECORD", "cveMetadata": {"state": "PUBLISHED", "cveId": "CVE-2026-31163", "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "assignerShortName": "mitre", "dateUpdated": "2026-04-23T19:04:19.232Z", "dateReserved": "2026-03-09T00:00:00.000Z", "datePublished": "2026-04-23T00:00:00.000Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "shortName": "mitre", "dateUpdated": "2026-04-23T18:15:19.470Z"}, "descriptions": [{"lang": "en", "value": "An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary commands via the dhcpMtu parameter to /cgi-bin/cstecgi.cgi."}], "affected": [{"vendor": "n/a", "product": "n/a", "versions": [{"version": "n/a", "status": "affected"}]}], "references": [{"url": "https://github.com/Svigo-o/TOTOLINK-Vul/tree/main/totolink-a3300r-dhcp-mtu-cmd-injection"}], "problemTypes": [{"descriptions": [{"type": "text", "lang": "en", "description": "n/a"}]}]}, "adp": [{"problemTypes": [{"descriptions": [{"type": "CWE", "cweId": "CWE-77", "lang": "en", "description": "CWE-77 Improper Neutralization of Special Elements used in a Command ('Command Injection')"}]}], "references": [{"url": "https://github.com/Svigo-o/TOTOLINK-Vul/tree/main/totolink-a3300r-dhcp-mtu-cmd-injection", "tags": ["exploit"]}], "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-04-23T19:03:43.690957Z", "id": "CVE-2026-31163", "options": [{"Exploitation": "poc"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-04-23T19:04:19.232Z"}}]}, "dataVersion": "5.2"}

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{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "17.0.0cu.557_B20221024"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "n/a", "source": "cna", "vendor": "n/a"}, "product": "a3300r_firmware", "vendor": "totolink"}], "analysis": {"en": {"generated_at": "2026-04-28T23:53:03.232166+00:00", "value": {"mitigation_remediation": ["Upgrade the device to a firmware version that fixes the command injection issue", "Disable or restrict access to the /cgi-bin/cstecgi.cgi endpoint when possible", "Apply network segmentation or firewall rules to block unauthorized access to the router\u2019s web interface"], "summary": {"action": "Apply Update", "impact": "Arbitrary command execution via the DHCP MTU parameter, enabling remote attackers to run arbitrary system commands on the device"}, "threat_synthesis": {"affected_systems": "The flaw affects only the ToToLink A3300R router running firmware version 17.0.0cu.557_B20221024. No other products or versions are listed as impacted.", "description_and_impact": "An OS command\u2011injection flaw in the ToToLink A3300R firmware allows an attacker to arbitrarily execute commands by supplying malicious input in the dhcpMtu parameter to the /cgi-bin/cstecgi.cgi endpoint. This vulnerability, identified as CWE\u201177, gives an attacker control over system commands, potentially leading to full device compromise. The CVE description does not specify authentication requirements, so it is unclear whether authentication is required for exploitation.", "risk_and_exploitability": "The CVSS score of 6.5 reflects moderate severity, while the EPSS score of less than 1% suggests a very low probability of exploitation in the wild. The flaw is not currently listed in the CISA KEV catalog. Based on the endpoint and parameter names, it is inferred that the attack is launched remotely over the network, but the CVE description does not state whether authentication is required."}}}}, "created": "2026-04-28T03:30:19.680355+00:00", "title": "Command Injection via DHCP MTU Parameter in ToToLink A3300R Firmware", "updated": "2026-04-29T00:00:13.829011+00:00", "vendors": ["totolink", "totolink$PRODUCT$a3300r_firmware"]}