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DEBIAN-CVE-2026-48690

Type: advisorySource: OSV1 source record

FastNetMon Community Edition through 1.2.9 contains an integer overflow vulnerability in the packet capture buffer allocation. In src/packet_storage.hpp, the allocate_buffer() function computes memory_size_in_bytes as 'buffer_size_in_packets * (max_captured_packet_size + sizeof(fastnetmon_pcap_pkthdr_t)) + sizeof(fastnetmon_pcap_file_header_t)' using unsigned int (32-bit) arithmetic. With max_captured_packet_size=1500 and sizeof(fastnetmon_pcap_pkthdr_t)=16, each packet requires approximately 1516 bytes. If buffer_size_in_packets exceeds approximately 2,832,542, the multiplication overflows, resulting in a much smaller allocation than expected. Subsequent write_packet() calls then write past the allocated buffer, causing heap corruption. The buffer_size_in_packets value is derived from the ban_details_records_count configuration parameter, which is parsed using atoi() with no overflow checking.

Announced Group revision 1
Original source ↗

DEBIAN-CVE-2026-48690

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: osv:DEBIAN-CVE-2026-48690

fastnetmon

Source reference: /affected/0/package/name

Affected versions
1.2.4-2

Source reference: /affected/0/versions

1.2.4-2+deb12u1

Source reference: /affected/0/versions

1.2.5-1

Source reference: /affected/0/versions

1.2.5-2

Source reference: /affected/0/versions

1.2.5-2~bpo12+1

Source reference: /affected/0/versions

1.2.6-1

Source reference: /affected/0/versions

1.2.6-1~bpo12+1

Source reference: /affected/0/versions

1.2.7-1

Source reference: /affected/0/versions

1.2.7-1~bpo12+1

Source reference: /affected/0/versions

1.2.8+git20250911-1

Source reference: /affected/0/versions

1.2.8+git20250911-2

Source reference: /affected/0/versions

1.2.8-1

Source reference: /affected/0/versions

1.2.8-1~bpo12+1

Source reference: /affected/0/versions

1.2.9-1

Source reference: /affected/0/versions

Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

fastnetmon

Source reference: /affected/1/package/name

Affected versions
1.2.8+git20250911-1

Source reference: /affected/1/versions

1.2.8+git20250911-2

Source reference: /affected/1/versions

1.2.8-1

Source reference: /affected/1/versions

Fixed versions
1.2.9-0+deb13u1

Source reference: /affected/1/ranges

Prerequisites
Not stated in this record

fastnetmon

Source reference: /affected/2/package/name

Affected versions
1.2.8+git20250911-1

Source reference: /affected/2/versions

1.2.8+git20250911-2

Source reference: /affected/2/versions

1.2.8-1

Source reference: /affected/2/versions

Fixed versions
1.2.9-1

Source reference: /affected/2/ranges

Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          }
        ]
      }
    ],
    "package": {
      "name": "fastnetmon",
      "purl": "pkg:deb/debian/fastnetmon?arch=source&distro=bookworm",
      "ecosystem": "Debian:12"
    },
    "versions": [
      "1.2.4-2",
      "1.2.4-2+deb12u1",
      "1.2.5-1",
      "1.2.5-2",
      "1.2.5-2~bpo12+1",
      "1.2.6-1",
      "1.2.6-1~bpo12+1",
      "1.2.7-1",
      "1.2.7-1~bpo12+1",
      "1.2.8+git20250911-1",
      "1.2.8+git20250911-2",
      "1.2.8-1",
      "1.2.8-1~bpo12+1",
      "1.2.9-1"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48690.json"
    },
    "ecosystem_specific": {
      "urgency": "unimportant"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
          {
            "fixed": "1.2.9-0+deb13u1"
          }
        ]
      }
    ],
    "package": {
      "name": "fastnetmon",
      "purl": "pkg:deb/debian/fastnetmon?arch=source&distro=trixie",
      "ecosystem": "Debian:13"
    },
    "versions": [
      "1.2.8+git20250911-1",
      "1.2.8+git20250911-2",
      "1.2.8-1"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48690.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
          {
            "fixed": "1.2.9-1"
          }
        ]
      }
    ],
    "package": {
      "name": "fastnetmon",
      "purl": "pkg:deb/debian/fastnetmon?arch=source&distro=forky",
      "ecosystem": "Debian:14"
    },
    "versions": [
      "1.2.8+git20250911-1",
      "1.2.8+git20250911-2",
      "1.2.8-1"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48690.json"
    },
    "ecosystem_specific": {
      "urgency": "unimportant"
    }
  }
]

Publisher severity

No explicit severity was provided.

Event
#57228 · Revision 1
Added to Heist Feed
Publisher date
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