How severe is CVE-2025-20209?

CVE-2025-20209 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-20209 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-20209?

CVE-2025-20209 primarily affects Cisco Ios Xr. In total, 40 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-20209?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-20209 have an EU (EUVD) identifier?

Yes. CVE-2025-20209 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-7579.

When was CVE-2025-20209 published?

CVE-2025-20209 was published on 2025-03-12 and last updated on 2026-06-17.

CVE-2025-20209

CVE-2025-20209 is a high-severity vulnerability in Cisco Ios Xr with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (40th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-7579
Weakness: CWE-770
Affected product: Cisco Ios Xr
Published: 2025-03-12
Last modified: 2026-06-17

Description

A vulnerability in the Internet Key Exchange version 2 (IKEv2) function of Cisco IOS XR Software could allow an unauthenticated, remote attacker to prevent an affected device from processing any control plane UDP packets.  This vulnerability is due to improper handling of malformed IKEv2 packets. An attacker could exploit this vulnerability by sending malformed IKEv2 packets to an affected device. A successful exploit could allow the attacker to prevent the affected device from processing any control plane UDP packets, resulting in a denial of service (DoS) condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

Frequently asked questions

What is CVE-2025-20209?: A vulnerability in the Internet Key Exchange version 2 (IKEv2) function of Cisco IOS XR Software could allow an unauthenticated, remote attacker to prevent an affected device from processing any control plane UDP packets.  This vulnerability is due to improper handling of malformed IKEv2 packets. An attacker could exploit this vulnerability by sending malformed IKEv2 packets to an affected device. A successful exploit could allow the attacker to prevent the affected device from processing any control plane UDP packets, resulting in a denial of service (DoS) condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
How severe is CVE-2025-20209?: CVE-2025-20209 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-20209 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-20209?: CVE-2025-20209 primarily affects Cisco Ios Xr. In total, 40 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-20209?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-20209 have an EU (EUVD) identifier?: Yes. CVE-2025-20209 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-7579.
When was CVE-2025-20209 published?: CVE-2025-20209 was published on 2025-03-12 and last updated on 2026-06-17.

References

Affected products (40)

cpe:2.3:o:cisco:ios_xr:6.5.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.5.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.5.3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.6.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.6.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.6.3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.6.25:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.0.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.0.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.0.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.1.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.1.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.2.0:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.2.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.2.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.3.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.3.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.3.27:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.4.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.4.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.5.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.5.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.6.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.6.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.7.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.7.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.7.21:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.8.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.8.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.8.22:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.9.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.9.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.10.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.10.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.11.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:7.11.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:24.1.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:24.1.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:24.2.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:24.2.11:*:*:*:*:*:*:*

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