CVE-2026-48684
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9...
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9 options template parser. In process_netflow_v9_options_template() (src/netflow_plugin/netflow_v9_collector.cpp), the scope parsing loop (lines 224-229) iterates until scopes_offset reaches the attacker-controlled option_scope_length value, reading netflow9_template_flowset_record_t structures at each step. No bounds check validates that (zone_address + scopes_offset + sizeof(record)) stays within the flowset. The same issue affects the options field loop (lines 241-257) with option_length. Furthermore, option_scope_length is not validated to be a multiple of sizeof(netflow9_template_flowset_record_t), potentially causing misaligned reads. An attacker can trigger reads past the end of the UDP packet buffer.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
NVD Score used
6.5
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9 options template parser. In process_netflow_v9_options_template() (src/netflow_plugin/netflow_v9_collector.cpp), the scope parsing loop (lines 224-229) iterates until scopes_offset reaches the attacker-controlled option_scope_length value, reading netflow9_template_flowset_record_t structures at each step. No bounds check validates that (zone_address + scopes_offset + sizeof(record)) stays within the flowset. The same issue affects the options field loop (lines 241-257) with option_length. Furthermore, option_scope_length is not validated to be a multiple of sizeof(netflow9_template_flowset_record_t), potentially causing misaligned reads. An attacker can trigger reads past the end of the UDP packet buffer.
- Record
CVE-2026-48684- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Weakness
- CWE-125
- Updated
- 2026-11-02
CVE List
6.5
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9 options template parser. In process_netflow_v9_options_template() (src/netflow_plugin/netflow_v9_collector.cpp), the scope parsing loop (lines 224-229) iterates until scopes_offset reaches the attacker-controlled option_scope_length value, reading netflow9_template_flowset_record_t structures at each step. No bounds check validates that (zone_address + scopes_offset + sizeof(record)) stays within the flowset. The same issue affects the options field loop (lines 241-257) with option_length. Furthermore, option_scope_length is not validated to be a multiple of sizeof(netflow9_template_flowset_record_t), potentially causing misaligned reads. An attacker can trigger reads past the end of the UDP packet buffer.
- Record
CVE-2026-48684- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Weakness
- CWE-125
- Updated
- 2026-11-02
EUVDEUVD-2026-31840
6.5
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9 options template parser. In process_netflow_v9_options_template() (src/netflow_plugin/netflow_v9_collector.cpp), the scope parsing loop (lines 224-229) iterates until scopes_offset reaches the attacker-controlled option_scope_length value, reading netflow9_template_flowset_record_t structures at each step. No bounds check validates that (zone_address + scopes_offset + sizeof(record)) stays within the flowset. The same issue affects the options field loop (lines 241-257) with option_length. Furthermore, option_scope_length is not validated to be a multiple of sizeof(netflow9_template_flowset_record_t), potentially causing misaligned reads. An attacker can trigger reads past the end of the UDP packet buffer.
- Record
EUVD-2026-31840- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6jf7-3j4w-4v3m
6.5
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9...
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9 options template parser. In process_netflow_v9_options_template() (src/netflow_plugin/netflow_v9_collector.cpp), the scope parsing loop (lines 224-229) iterates until scopes_offset reaches the attacker-controlled option_scope_length value, reading netflow9_template_flowset_record_t structures at each step. No bounds check validates that (zone_address + scopes_offset + sizeof(record)) stays within the flowset. The same issue affects the options field loop (lines 241-257) with option_length. Furthermore, option_scope_length is not validated to be a multiple of sizeof(netflow9_template_flowset_record_t), potentially causing misaligned reads. An attacker can trigger reads past the end of the UDP packet buffer.
- Record
GHSA-6jf7-3j4w-4v3m- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Weakness
- CWE-125
- Updated
- 2026-11-02
OSV
6.5
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9 options template parser. In process_netflow_v9_options_template() (src/netflow_plugin/netflow_v9_collector.cpp), the scope parsing loop (lines 224-229) iterates until scopes_offset reaches the attacker-controlled option_scope_length value, reading netflow9_template_flowset_record_t structures at each step. No bounds check validates that (zone_address + scopes_offset + sizeof(record)) stays within the flowset. The same issue affects the options field loop (lines 241-257) with option_length. Furthermore, option_scope_length is not validated to be a multiple of sizeof(netflow9_template_flowset_record_t), potentially causing misaligned reads. An attacker can trigger reads past the end of the UDP packet buffer.
- Record
CVE-2026-48684- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-48684
6.5
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9 options template parser. In process_netflow_v9_options_template() (src/netflow_plugin/netflow_v9_collector.cpp), the scope parsing loop (lines 224-229) iterates until scopes_offset reaches the attacker-controlled option_scope_length value, reading netflow9_template_flowset_record_t structures at each step. No bounds check validates that (zone_address + scopes_offset + sizeof(record)) stays within the flowset. The same issue affects the options field loop (lines 241-257) with option_length. Furthermore, option_scope_length is not validated to be a multiple of sizeof(netflow9_template_flowset_record_t), potentially causing misaligned reads. An attacker can trigger reads past the end of the UDP packet buffer.
- Record
DEBIAN-CVE-2026-48684- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-48684
6.5
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the NetFlow v9 options template parser. In process_netflow_v9_options_template() (src/netflow_plugin/netflow_v9_collector.cpp), the scope parsing loop (lines 224-229) iterates until scopes_offset reaches the attacker-controlled option_scope_length value, reading netflow9_template_flowset_record_t structures at each step. No bounds check validates that (zone_address + scopes_offset + sizeof(record)) stays within the flowset. The same issue affects the options field loop (lines 241-257) with option_length. Furthermore, option_scope_length is not validated to be a multiple of sizeof(netflow9_template_flowset_record_t), potentially causing misaligned reads. An attacker can trigger reads past the end of the UDP packet buffer.
- Record
UBUNTU-CVE-2026-48684- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
fastnetmonDebian:12 |
All versions, plus listed versions 1.2.4-21.2.4-2+deb12u11.2.5-11.2.5-21.2.5-2~bpo12+1 Show 9 moreShow less1.2.6-11.2.6-1~bpo12+11.2.7-11.2.7-1~bpo12+11.2.8+git20250911-11.2.8+git20250911-21.2.8-11.2.8-1~bpo12+11.2.9-1 |
None known |
fastnetmonDebian:13 |
before 1.2.9-0+deb13u1, plus listed versions 1.2.8+git20250911-11.2.8+git20250911-21.2.8-1 |
1.2.9-0+deb13u1 |
fastnetmonDebian:14 |
before 1.2.9-1, plus listed versions 1.2.8+git20250911-11.2.8+git20250911-21.2.8-1 |
1.2.9-1 |
fastnetmonUbuntu:18.04:LTS |
All versions, plus listed versions 1.1.3+dfsg-31.1.3+dfsg-41.1.3+dfsg-6build1 |
None known |
fastnetmonUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 1.1.4-11.1.4-1build31.1.4-1build41.1.4-1build51.1.4-1ubuntu0.1~esm1 |
None known |
fastnetmonUbuntu:Pro:24.04:LTS |
All versions, plus listed versions 1.2.5-11.2.6-11.2.6-1build11.2.6-1build21.2.6-1build31.2.6-1build41.2.6-1ubuntu0.1~esm1 |
None known |
fastnetmonUbuntu:25.10 |
All versions, plus listed versions 1.2.8-1build11.2.8-1build21.2.8+git20250911-1 |
None known |
fastnetmonUbuntu:26.10 |
All versions, plus listed versions 1.2.8+git20250911-21.2.9-11.2.9-1build11.2.9-1build2 |
None known |
fastnetmonUbuntu:Pro:26.04:LTS |
All versions, plus listed versions 1.2.8+git20250911-11.2.8+git20250911-1build11.2.8+git20250911-1build21.2.8+git20250911-21.2.8+git20250911-2ubuntu0.1~esm1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-48684 is a medium vulnerability (CVSS 6.5) in Pavel-odintsov Fastnetmon, published May 26, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.26%, the 18th percentile. Fixed in fastnetmon 1.2.9-0+deb13u1.
References
github.com/pavel-odintsov/fastnetmon
github.com/pavel-odintsov/fastnetmon/blob/master/src/netflow_plugin/netflow_v9_collector.cpp
lorikeetsecurity.com/blog/fastnetmon-cve-2026-48684-netflow-v9-options-oob
nvd.nist.gov/vuln/detail/CVE-2026-48684
github.com/advisories/GHSA-6jf7-3j4w-4v3m
github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48684.json