Vulnerability · CVE-2025-20239
A vulnerability in the Internet Key Exchange Version 2 (IKEv2) feature of Cisco IOS Software, IOS XE Software, Secure Firewall Adaptive Security Appliance (ASA) Software, and Secur
Published Aug 14, 2025 · catalog updated Aug 14, 2025 · Cisco IOS
Last checked Oct 24, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2025-20239. EPSS is 0.62%. Act only if a listed version of Cisco IOS is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
Same product and reporting
- CVE-2025-20149 · Medium
- CVE-2025-20327 · High
- CVE-2000-0984 · Unknown · known exploited
- CVE-2025-20164 · High
- CVE-2001-0537 · Unknown · known exploited
- Severity
- High8.6
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.62%
- Remediation
- Advisory link
- Affected products
- vendor Cisco IOS 15.6(2)T1
A vulnerability in the Internet Key Exchange Version 2 (IKEv2) feature of Cisco IOS Software, IOS XE Software, Secure Firewall Adaptive Security Appliance (ASA) Software, and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a memory leak, resulting in a denial of service (DoS) condition. This vulnerability is due to a lack of proper processing of IKEv2 packets. An attacker could exploit this vulnerability by sending crafted IKEv2 packets to an affected device. In the case of Cisco IOS and IOS XE Software, a successful exploit could allow
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor Cisco IOS 15.6(2)T115.6(2)T1
How to fix CVE-2025-20239
No stored fix
No vendor fix text is stored. Use the linked advisory before you change production.
Version check
Seen in 15.6(2)T1
Advisory
Open the cve_org record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2025-20239. EPSS is 0.62%. Act only if a listed version of Cisco IOS is installed.
Which versions are affected?
Compare what you have installed with Cisco IOS 15.6(2)T1 15.6(2)T1. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.62%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Technology hubs
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Aug 14, 2025 · EUVD
Detected
A vulnerability in the Internet Key Exchange Version 2 (IKEv2) feature of Cisco IOS Software, IOS XE Software, Secure Firewall Adaptive Security Appliance (ASA) Software, and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a memory leak, resulting in a denial of service (DoS) condition. This vulnerability is due to a lack of proper processin
Aug 14, 2025 · EUVD
Updated
A vulnerability in the Internet Key Exchange Version 2 (IKEv2) feature of Cisco IOS Software, IOS XE Software, Secure Firewall Adaptive Security Appliance (ASA) Software, and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a memory leak, resulting in a denial of service (DoS) condition. This vulnerability is due to a lack of proper processin
Sources
- CVE.orgVulnerability recordCVE-2025-20239
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2025-20239
30-day exploitation probability 0.62%
first.org - EUVDVulnerability recordEUVD-2025-24874
A vulnerability in the Internet Key Exchange Version 2 (IKEv2) feature of Cisco IOS Software, IOS XE Software, Secure Firewall Adaptive Security Appliance (ASA) Software, and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Oct 24, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- FIRST EPSSOct 24, 2026
- CVE.orgOct 21, 2026
- EUVDOct 20, 2026