CVSS 4.0
6.0 mediumCVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:L/VI:H/VA:H/SC:N/SI:N/SA:NCVE-2026-129217 bgpd: out-of-bounds heap read and crash on NOTIFICATION Cease/Hard Reset with one data byte
Medium (6.0) in frrouting frrouting.
On this page
In FRRouting (FRR) 8.3 through 10.5.1, bgp_notify_decapsulate_hard_reset() in bgpd/bgp_packet.c does not validate the length of the data field of a received BGP NOTIFICATION Cease/Hard Reset message (RFC 8538). When the data field is exactly one byte long, the function reads one byte past the end of a heap buffer and the 16-bit length of the encapsulated data underflows to 65535, causing a 65535-byte out-of-bounds heap read followed by an assertion failure. A remote BGP peer that has established a session and negotiated the Graceful Restart capability with the Notification (N) bit can send such a message to crash the bgpd daemon, terminating all BGP sessions (denial of service). This is fixed in 10.0.5, 10.1.5, 10.2.6, 10.3.4, 10.4.3, 10.5.2 and 10.6.0.
Severity
- Published
- Assigned by
- NetDEF (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| FRRouting | from 10.5.0 before 10.5.2 |
| FRRouting | from 10.4.0 before 10.4.3 |
| FRRouting | from 10.3 before 10.3.4 |
| FRRouting | from 10.2 before 10.2.6 |
| FRRouting | from 10.1 before 10.1.5 |
| FRRouting | from 8.3 before 10.0.5 |
Attack patterns (CAPEC)
- CAPEC-540 Overread Buffers Likelihood: Low · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.