{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "Nmap",
          "vendor": "Nmap",
          "versions": [
            {
              "status": "affected",
              "version": "unknown"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "advisories"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "----------------------------------------------------------------------------\nNotCVE Advisory \u2014 NotCVE-2026-0011\n----------------------------------------------------------------------------\n\n[-] Summary:\nNmap 7.99 and earlier contain a loop with an unreachable exit condition in\nthe Packet:parse_options() method of nselib/packet.lua. A remote host that\nis the target of a scan can exhaust the memory of the scanning Nmap process\nand terminate it by replying with a packet that carries a zero-length header\noption. No authentication and no access to the scanning machine are\nrequired: the attacker only needs to be scanned.\nCVSS:3.1 6.5 (AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H).\n\n[-] Affected:\nNmap, versions 7.99 and earlier (nselib/packet.lua).\nFixed in commit 7ef4ee0 (2026-06-11). That fix sits above the topmost\nrelease header in the CHANGELOG (Nmap 7.99 [2026-03-26]), so as of this\nwriting it is present only in the development tree and no released version\ncarrying it has been verified.\n\n[-] Technical Description:\nPacket:parse_options(offset, length) walks the option area with a cursor,\nopt_ptr, reading an option type t and, for any type other than 0 (End of\nOption List) or 1 (No-Operation), a length byte l taken from\nself:u8(offset + opt_ptr + 1). The cursor is then advanced by\nopt_ptr = opt_ptr + l.\n\nBefore commit 7ef4ee0 the parser accepted l == 0 without validation, so the\ncursor never advanced and the \"while opt_ptr \u003c length\" condition never\nbecame false. Because the loop body allocated a fresh table with\noptions[op] = {} and incremented op on every pass, the non-terminating loop\nalso grew a table without bound, and the Lua interpreter embedded in Nmap\nconsumed memory until the process died. The options[op] = {} assignment was\npositioned before the length was validated, which is why the loop allocated\nrather than merely spinning.\n\nThe method is reached from tcp_parse(), where the option area length derives\nfrom the TCP data offset field of the received packet. A remote peer\ntherefore controls both the length of the option area and its contents.\nnselib/packet.lua is the packet-dissection library used by NSE scripts that\ncapture and parse raw packets, so exploitation requires the operator to run\na scan that loads such a script against a host the attacker controls.\n\nNothing is persisted and the effect ends with the process, but the attacker\ncan repeat it on every subsequent scan, so the host remains effectively\nunscannable by any script using this library.\n\nCommit 7ef4ee0 (\"Stop parsing on a zero-length packet option\") adds an\n\"if l==0 then break end\" guard before any allocation and moves the\noptions[op] = {} initialisation to after that check. The CHANGELOG entry\nreads \"[NSE][GH#3368] Fixed an out-of-memory issue in packet.lua when\nparsing a zero-length TCP header option.\"\n\nThe step-by-step attack path, the reachability analysis of the IP options\ncode path and the full write-up are published at the advisory URL below.\n\nWeaknesses:\nCWE-835: Loop with Unreachable Exit Condition (\u0027Infinite Loop\u0027)\nCWE-400: Uncontrolled Resource Consumption\nCWE-770: Allocation of Resources Without Limits or Throttling\nCAPEC-130: Excessive Allocation\n\n[-] Timeline:\n[28/07/2026] - NotCVE ID reserved.\n[28/07/2026] - Published as NotCVE-2026-0011.\n\n[-] Credit:\nDiscovered by Maxim Suhanov (@errno_fail).\n\n[-] Full Details and Updates:\nhttps://notcve.org/notcve/NotCVE-2026-0011\n\n[-] References:\nhttps://github.com/nmap/nmap/issues/3368\nhttps://github.com/nmap/nmap/commit/7ef4ee030a0023fe22616387a000032e1a678b6a\nhttps://github.com/nmap/nmap/pull/3373\nhttps://raw.githubusercontent.com/nmap/nmap/master/nselib/packet.lua\nhttps://raw.githubusercontent.com/nmap/nmap/master/CHANGELOG\n\n[-] About NotCVE:\nNotCVE (https://notcve.org) assigns public, timestamped NotCVE IDs to\nvulnerabilities not acknowledged by vendors. Vendor will not assign a CVE?\nRequest a NotCVE: https://notcve.org/form/ \u00b7 Contributors:\nhttps://notcve.org/hall/\n_______________________________________________\nSent through the Full Disclosure mailing list\nhttps://nmap.org/mailman/listinfo/fulldisclosure\nWeb Archives \u0026 RSS: https://seclists.org/fulldisclosure/"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-400",
              "description": "CWE-400",
              "lang": "en",
              "type": "CWE"
            },
            {
              "cweId": "CWE-770",
              "description": "CWE-770",
              "lang": "en",
              "type": "CWE"
            },
            {
              "cweId": "CWE-835",
              "description": "CWE-835",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-11T08:13:27Z",
        "orgId": "4e2abfbf-4a2a-4b76-a4e0-d77c18ba156c",
        "shortName": "VULNARCHIVE"
      },
      "references": [
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://vuln.freearchive.org/archive/full-disclosure/2026/Aug/112"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://seclists.org/fulldisclosure/2026/Aug/112"
        },
        {
          "url": "https://github.com/nmap/nmap/commit/7ef4ee030a0023fe22616387a000032e1a678b6a"
        },
        {
          "url": "https://github.com/nmap/nmap/issues/3368"
        },
        {
          "url": "https://github.com/nmap/nmap/pull/3373"
        },
        {
          "url": "https://nmap.org/mailman/listinfo/fulldisclosure"
        },
        {
          "url": "https://notcve.org"
        },
        {
          "url": "https://notcve.org/form/"
        },
        {
          "url": "https://notcve.org/hall/"
        },
        {
          "url": "https://notcve.org/notcve/NotCVE-2026-0011"
        },
        {
          "url": "https://raw.githubusercontent.com/nmap/nmap/master/CHANGELOG"
        },
        {
          "url": "https://raw.githubusercontent.com/nmap/nmap/master/nselib/packet.lua"
        },
        {
          "url": "https://seclists.org/fulldisclosure/"
        }
      ],
      "source": {
        "defect": [
          "https://seclists.org/fulldisclosure/2026/Aug/112"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "[NotCVE-2026-0011] Nmap 7.99 and Earlier nselib/packet.lua Zero-Length TCP Option Infinite Loop Allows Remote Denial of Service",
      "x_gcve": [
        {
          "recordType": "advisory",
          "relationships": [],
          "vulnId": "GCVE-1988-2026-0155",
          "x_vulnarchive": {
            "archiveUrl": "https://vuln.freearchive.org/archive/full-disclosure/2026/Aug/112",
            "automated": true,
            "contentSha256": "526e75db3e65ed78ab707f18bcdbc6de452e1ba09cb695995dc1e4c091bc7ef1",
            "evidenceScore": 8,
            "messageId": "",
            "originalUrl": "https://seclists.org/fulldisclosure/2026/Aug/112",
            "policy": "vulnarchive-1",
            "sourceFormat": "text/html",
            "sourcePublishedAt": "2026-08-19T10:57:53Z"
          }
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      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "4e2abfbf-4a2a-4b76-a4e0-d77c18ba156c",
    "assignerShortName": "VULNARCHIVE",
    "datePublished": "2026-09-07T13:20:22Z",
    "dateUpdated": "2026-09-11T08:13:27Z",
    "state": "PUBLISHED",
    "vulnId": "GCVE-1988-2026-0155"
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  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}