CVE-2025-61101VulnerabilityPublished 27 Oct 2025Updated 28 Oct 2025

CVE-2025-61101: frr · n/a

Affects frrSource CVE Database V5

Not known to be exploited · CVSS 7.5 High.

Data as of 26 Oct 2026, 08:30 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.5% chance of exploitation in 30 days – higher than 42% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 27 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
GitHubfrrouting/frr`pkg:github/frrouting/frr`Other threats	Affected >=4.0 <=10.4.1	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

To mitigate CVE-2025-61101, organizations should monitor FRRouting vendor channels for official patches or updates addressing this vulnerability and apply them promptly once available. In the absence of a patch, network administrators should consider implementing filtering rules to block or restrict OSPF packets from untrusted sources, limiting exposure to crafted malicious packets. Network segmentation and strict control of routing protocol exchanges can reduce the attack surface. Employing intrusion detection or prevention systems (IDS/IPS) capable of detecting anomalous OSPF traffic patterns may help identify and block exploitation attempts. Regularly auditing network devices and routing software versions to ensure they are up to date and supported is critical. Additionally, maintaining robust network monitoring to quickly detect routing daemon crashes or instability can enable rapid response and mitigation. Organizations should also review their incident response plans to include scenarios involving routing protocol DoS attacks. Collaboration with upstream providers and peers to ensure OSPF traffic integrity can further reduce risk.

Description

FRRouting/frr from v4.0 through v10.4.1 was discovered to contain a NULL pointer dereference via the show_vty_ext_link_rmt_itf_addr function at ospf_ext.c. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted OSPF packet.

Impact

For European organizations, the impact of CVE-2025-61101 can be significant, especially for those relying on FRRouting for OSPF-based routing in their network infrastructure. A successful exploit can cause the FRR daemon to crash, resulting in loss of routing information and network outages. This can disrupt business operations, degrade service availability, and potentially cause cascading failures in interconnected networks. Telecommunications providers, cloud service operators, and large enterprises with complex network topologies are particularly at risk. The disruption of OSPF routing can lead to packet loss, increased latency, and failure of critical applications dependent on network connectivity. Additionally, the lack of confidentiality or integrity impact means data theft or manipulation is unlikely, but the availability impact alone can cause severe operational and financial consequences. Given the vulnerability can be exploited remotely without authentication, attackers can launch DoS attacks from within or outside the network perimeter, increasing the threat surface. European critical infrastructure sectors, including finance, healthcare, and government networks, may face heightened risk if FRRouting is part of their routing stack.

CWE-476NULL Pointer Dereference (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #13OWASP Top 10 A10:2025: Mishandling of Exceptional Conditions (opens in a new tab)
The product dereferences a pointer that it expects to be valid but is NULL.
Implementation
For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
Requirements
Select a programming language that is not susceptible to these issues.
Implementation
Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
OWASP Cheat Sheets
Logging (opens in a new tab)
Error Handling (opens in a new tab)
OWASP ASVS 4.0.3
V11.1.7 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 4 Nov 2025, 03:17 UTC

WeaknessesCWE-476

Technical details

References

Community reviews

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