Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software IKEv1 Denial of Service Vulnerability
A vulnerability in the Internet Key Exchange version 1 (IKEv1) feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper management of system memory. An attacker could exploit this vulnerability by sending malicious IKEv1 traffic to an affected device. The attacker does not need valid credentials to authenticate the VPN session, nor does the attacker's source address need to match a peer statement in the crypto map applied to the ingress interface of the affected device. An exploit could allow the attacker to exhaust system memory resources, leading to a reload of an affected device.
- Published
- Oct 2, 2019
- Updated
- Aug 11, 2026
- EPSS
- 2.0% · 80th percentile
- CWE
- CWE-399
Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.
Report tools
Action score
35
Monitor
Low priority for now.
- CVSS
- 34 / 40 · 8.6 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 2.0%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 8.6
- CNA · cisco
- 8.6
- agree
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| cisco | adaptive security appliance software | cpe:2.3:a:cisco:adaptive_security_appliance_software |
| cisco | secure firewall threat defense | cpe:2.3:a:cisco:secure_firewall_threat_defense |
| cisco | asa 5505 firmware | cpe:2.3:o:cisco:asa_5505_firmware |
| cisco | asa 5505 | cpe:2.3:h:cisco:asa_5505 |
| cisco | asa 5510 firmware | cpe:2.3:o:cisco:asa_5510_firmware |
| cisco | asa 5510 | cpe:2.3:h:cisco:asa_5510 |
| cisco | asa 5512-x firmware | cpe:2.3:o:cisco:asa_5512-x_firmware |
| cisco | asa 5512-x | cpe:2.3:h:cisco:asa_5512-x |
| cisco | asa 5515-x firmware | cpe:2.3:o:cisco:asa_5515-x_firmware |
| cisco | asa 5515-x | cpe:2.3:h:cisco:asa_5515-x |
| cisco | asa 5520 firmware | cpe:2.3:o:cisco:asa_5520_firmware |
| cisco | asa 5520 | cpe:2.3:h:cisco:asa_5520 |
and 12 more
Using adaptive security appliance software? Add it to your stack and be the first to know about CVEs like this one. (Firewall)
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cisco adaptive security appliance software9.7 and later · before 9.8.4.10
- cisco adaptive security appliance software9.9 and later · before 9.9.2.47
- cisco adaptive security appliance software9.10 and later · before 9.10.1.30
- cisco adaptive security appliance software9.12 and later · before 9.12.2.5
Versions reported by the vendor
Affected version ranges reported by the assigning authority (cisco). Independent of NVD's CPE analysis and usually ahead of it.
Cisco Cisco Adaptive Security Appliance (ASA) Software
- unspecified and later · before n/aaffected
Same product
cisco: all recordsOther highest-scoring records for the same primary product.
- CVE-2025-20362Update: On November 5, 2025, Cisco became aware of a new attack variant against devices running Cisco Secure ASA Software or Cisco Secure FTKEV90Now
- CVE-2025-20333A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat DKEV90Now
- CVE-2020-3452Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Read-Only Path Traversal VulnerabilityKEV90Now
- CVE-2018-0296A vulnerability in the web interface of the Cisco Adaptive Security Appliance (ASA) could allow an unauthenticated, remote attacker to causeKEV90Now
- CVE-2024-20353A vulnerability in the management and VPN web servers for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat DefensKEV85Now
- CVE-2023-20269A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTDKEV74This week
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
Impact can extend beyond the vulnerable component (scope changes).
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-399 · Resource Management ErrorsCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
Vendor advisories and official records. Exploit/PoC links are deliberately left out.