TI-2026-35976 Aliases CVE-2026-48691 GHSA-pjmc-gjwh-qr2w

FastNetMon Community Edition through 1.2.9 contains an integer overflow in the BGP…

MEDIUM 48CWE-122Published 2026-05-26 · Updated 2026-05-27

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Code execution
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-122 and the CVSS impact.

Summary

FastNetMon Community Edition through 1.2.9 contains an integer overflow in the BGP AS_PATH attribute encoder. In src/bgp_protocol.hpp, the IPv4UnicastAnnounce::get_attributes() function computes attribute_length as 'sizeof(bgp_as_path_segment_element_t) + this->as_path_asns.size() * sizeof(uint32_t)' and stores it in a uint8_t field (line 600-605). Since uint8_t can only hold values 0-255, an AS_PATH containing more than 63 ASNs (2 + 64*4 = 258 > 255) causes silent truncation. The truncated length is used for buffer sizing, while the actual data written is the full untruncated amount, resulting in a heap buffer overflow. Similarly, the path_segment_length field at line 621 is also uint8_t, truncating with more than 255 ASNs.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00308 23rd percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:pavel-odintsov:fastnetmon:::::community:::*	up to 1.2.9	Vulnerable	pavel-odintsov

cpe:2.3:a:pavel-odintsov:fastnetmon:*:*:*:*:community:*:*:* Versions up to 1.2.9 Vulnerable ·pavel-odintsov

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product

Red Hat

Timeline

2026-10-02 Threatist record created from CVE-2026-48691
2026-10-03 Alias added: GHSA-pjmc-gjwh-qr2w

References

Advisory 1

https://lorikeetsecurity.com/blog/fastnetmon-cve-2026-48691-bgp-as-path-overflow

Other 2

TI-2026-35974 FastNetMon Community Edition through 1.2.9 contains an off-by-one heap-based buffer… CVSS 3.1CRITICAL 9.8
TI-2026-35971 FastNetMon Community Edition through 1.2.9 contains a stack-based buffer overflow in the… CVSS 3.1CRITICAL 9.8
TI-2026-35972 FastNetMon Community Edition through 1.2.9 contains an OS command injection vulnerability… CVSS 3.1CRITICAL 9.8
TI-2024-37109 An issue was discovered in FastNetMon Community Edition through 1.2.7. CVSS 3.1HIGH 7.5
TI-2024-37108 An issue was discovered in FastNetMon Community Edition through 1.2.7. CVSS 3.1HIGH 7.5
TI-2026-35980 FastNetMon Community Edition through 1.2.9 contains an OS command injection vulnerability… CVSS 3.1HIGH 8.1

See all 15 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences