CVE-2026-119776

Read full description

In all prior released versions of FRRouting, the OSPFv3 (for IPv6) implementation does not check that OSPFv3 packets have a link-local source address and either a link-local destination or one of the protocol multicast destination groups. This may enable malicious actors to establish OSPFv3 adjacencies from unexpectedly, distant IPv6 hosts. Proper usage of OSPFv3 authentication trailers (RFC 7166, as is best practice) prevents full exploitation of this issue, though may allow a malicious actor to waste CPU on authentication checks. Note the linked PR #23935 is not sufficient to fix the issue as it only verifies the source address. It is the destination address that must be checked. Required configuration: The OSPFv3 for IPv6 routing protocol must be running (ospf6d process) and in use (enabled globally with "router ospf6" and on specific interfaces with "ipv6 ospf6 area".) Workaround: either: * configure OSPFv3 authentication trailers ("ipv6 ospf6 authentication") * or ensure through firewall configuration that only packets with link-local or multicast destination addresses are accepted on input for IPv6 protocol 89 (OSPF). Note that checking the source address is insufficient, as some routers may (unexpectedly) forward packets with global-scoped IPv6 destination addresses even if they have link-local source addresses.

CVSS 6.1 (MEDIUM)

Attention and evidence

HYPE SCORE

0.0/10

REALITY · THREAT PRIORITY

2.1/10

General review priority; not probability

Evidence confidence: Insufficient evidence

Why this priority?

Technical severity: CVSS 6.1: +2.13
Fresh EPSS: 0.40%: +0.01

General review priority, not probability, victim count or asset-specific risk. A range covers missing CVSS/EPSS inputs within the current evidence state.

Sources: 1 documents and public datasets.

Hype components

Headline sample (25%)

0/100

Press, 30 days (60%)

0/100

Grounded branding (15%)

0/100

HYPE TOTAL0/100

Sources and documents

Latest Vulnerabilities

Technical advisory · 04 Nov 2026, 14:15 · CVE-2026-119776 - FRRouting OSPFv3 Improper Input Validation Vulnerability

Score evolution

● Hype ● Reality

━ Hype Score (Perceived) ━ Reality threat priority. Definition changes are not new attacks.

Public exploit evidence

Public exploit entries / repo candidates

Evidence context and dated references

Reality is general threat/review priority, combining observed exploitation, CVSS severity and fresh EPSS. Evidence confidence is separate. This is not calibrated risk, a victim count or an asset-specific assessment. A range reflects missing numeric inputs. Published 3 days ago. Exploitation evidence usually takes weeks to show up: a low reality score can mean there is no data yet, not that the flaw is mild.

Evidence in context

Confidence in exploitation evidence: Insufficient evidence
Priority basis: Exploitation in attacks unconfirmed; CVSS 6.1; EPSS 0.4%
Attention, last 30 days: 0 distinct story titles; 0 press documents; 0 publisher domains.
Technical potential: network access, low privileges, no user interaction, additional attack conditions.
Observed activity: No exploitation observation is recorded.
Known scale: Not quantified.
Evidence confidence basis: Insufficient evidence

Score evaluated: 2026-11-05 13:59:55.835577+00:00 · EPSS snapshot: 2026-11-05T12:03:04Z

Source event timeline

Published

04 Nov 2026, 14:15

Score calculated

05 Nov 2026, 13:59