CVE-2026-92698
FastNetMon: sFlow header_size field trusted as parser capture length causes remote out-of-bounds read
FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, process_sflow_flow_sample() in src/sflow_plugin/sflow_collector.cpp passes the attacker-controlled sflow_raw_protocol_header_t.header_size to parse_raw_packet_to_simple_packet_full() as its trusted captured length without comparing it with the bytes remaining in the record. An inflated header_size creates a false end pointer beyond the received sFlow v5 UDP buffer, defeating the nested parser's bounds checks and causing an unauthenticated remote out-of-bounds read and process crash, with possible limited exposure of adjacent bytes through parsed flow fields. No fixed release is available as of this review.
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
- High
Exploit likelihood
What each source reports
CVE List Score used
8.2
FastNetMon: sFlow header_size field trusted as parser capture length causes remote out-of-bounds read
FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, process_sflow_flow_sample() in src/sflow_plugin/sflow_collector.cpp passes the attacker-controlled sflow_raw_protocol_header_t.header_size to parse_raw_packet_to_simple_packet_full() as its trusted captured length without comparing it with the bytes remaining in the record. An inflated header_size creates a false end pointer beyond the received sFlow v5 UDP buffer, defeating the nested parser's bounds checks and causing an unauthenticated remote out-of-bounds read and process crash, with possible limited exposure of adjacent bytes through parsed flow fields. No fixed release is available as of this review.
- Record
CVE-2026-92698- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - Weakness
- CWE-125
- Updated
- 2026-11-05
EUVDEUVD-2026-117874
8.2
FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, process_sflow_flow_sample() in src/sflow_plugin/sflow_collector.cpp passes the attacker-controlled sflow_raw_protocol_header_t.header_size to parse_raw_packet_to_simple_packet_full() as its trusted captured length without comparing it with the bytes remaining in the record. An inflated header_size creates a false end pointer beyond the received sFlow v5 UDP buffer, defeating the nested parser's bounds checks and causing an unauthenticated remote out-of-bounds read and process crash, with possible limited exposure of adjacent bytes through parsed flow fields. No fixed release is available as of this review.
- Record
EUVD-2026-117874- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - Updated
- 2026-11-06
NVD
8.2
FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, process_sflow_flow_sample() in src/sflow_plugin/sflow_collector.cpp passes the attacker-controlled sflow_raw_protocol_header_t.header_size to parse_raw_packet_to_simple_packet_full() as its trusted captured length without comparing it with the bytes remaining in the record. An inflated header_size creates a false end pointer beyond the received sFlow v5 UDP buffer, defeating the nested parser's bounds checks and causing an unauthenticated remote out-of-bounds read and process crash, with possible limited exposure of adjacent bytes through parsed flow fields. No fixed release is available as of this review.
- Record
CVE-2026-92698- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - Weakness
- CWE-125
- Updated
- 2026-11-06
OSV
8.2
FastNetMon: sFlow header_size field trusted as parser capture length causes remote out-of-bounds read
FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, process_sflow_flow_sample() in src/sflow_plugin/sflow_collector.cpp passes the attacker-controlled sflow_raw_protocol_header_t.header_size to parse_raw_packet_to_simple_packet_full() as its trusted captured length without comparing it with the bytes remaining in the record. An inflated header_size creates a false end pointer beyond the received sFlow v5 UDP buffer, defeating the nested parser's bounds checks and causing an unauthenticated remote out-of-bounds read and process crash, with possible limited exposure of adjacent bytes through parsed flow fields. No fixed release is available as of this review.
- Record
CVE-2026-92698- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - Weakness
- CWE-125
- Updated
- 2026-11-07
OSVDEBIAN-CVE-2026-92698
8.2
FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, process_sflow_flow_sample() in src/sflow_plugin/sflow_collector.cpp passes the attacker-controlled sflow_raw_protocol_header_t.header_size to parse_raw_packet_to_simple_packet_full() as its trusted captured length without comparing it with the bytes remaining in the record. An inflated header_size creates a false end pointer beyond the received sFlow v5 UDP buffer, defeating the nested parser's bounds checks and causing an unauthenticated remote out-of-bounds read and process crash, with possible limited exposure of adjacent bytes through parsed flow fields. No fixed release is available as of this review.
- Record
DEBIAN-CVE-2026-92698- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - Updated
- 2026-11-06
OSVUBUNTU-CVE-2026-92698
8.2
FastNetMon is a high-performance DDoS detector and sensor. In version 1.2.9 and earlier, process_sflow_flow_sample() in src/sflow_plugin/sflow_collector.cpp passes the attacker-controlled sflow_raw_protocol_header_t.header_size to parse_raw_packet_to_simple_packet_full() as its trusted captured length without comparing it with the bytes remaining in the record. An inflated header_size creates a false end pointer beyond the received sFlow v5 UDP buffer, defeating the nested parser's bounds checks and causing an unauthenticated remote out-of-bounds read and process crash, with possible limited exposure of adjacent bytes through parsed flow fields. No fixed release is available as of this review.
- Record
UBUNTU-CVE-2026-92698- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - Updated
- 2026-11-07
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 |
All versions, plus listed versions 1.2.8+git20250911-11.2.8+git20250911-21.2.8-11.2.9-0+deb13u11.2.9-1 |
None known |
fastnetmonDebian:14 |
All versions, plus listed versions 1.2.8+git20250911-11.2.8+git20250911-21.2.8-11.2.9-1 |
None known |
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: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 |
|---|---|---|
| affected, aliases, references | OSV | |
| aliases, references | OSV | |
| affected, aliases, references | NVD, OSV | |
| aliases, published | EUVD | |
| first indexed | CVE List |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-92698 is a high vulnerability (CVSS 8.2) in Pavel-odintsov Fastnetmon, published November 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.32%, the 25th percentile. No source names a fixed version.
References
github.com/pavel-odintsov/fastnetmon/security/advisories/GHSA-852r-3wcv-pjx2
github.com/pavel-odintsov/fastnetmon/pull/1089
github.com/pavel-odintsov/fastnetmon/pull/1093
github.com/pavel-odintsov/fastnetmon/commit/6871b7383322db14405a8de1399a83da15ef3533
github.com/pavel-odintsov/fastnetmon/commit/be81c403b9aa891f8444a6379cd4a4fbbc324a83
github.com/CVEProject/cvelistV5/tree/main/cves/2026/92xxx/CVE-2026-92698.json