CVE-2025-20134 (GCVE-0-2025-20134)
Vulnerability from cvelistv5 – Published: 2025-08-14 16:28 – Updated: 2025-08-19 21:41
VLAI
EPSS
VEX
Title
Cisco Adaptive Security Appliance and Firepower Threat Defense Software SSL/TLS Certificate Denial of Service Vulnerability
Summary
A vulnerability in the certificate processing of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.
This vulnerability is due to improper parsing of SSL/TLS certificates. An attacker could exploit this vulnerability by sending crafted DNS packets that match a static Network Address Translation (NAT) rule with DNS inspection enabled through an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Severity
8.6 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-08-14 18:42 UTC
CWE
- CWE-415 - Double Free
Assigner
References
1 reference
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Cisco | Cisco Adaptive Security Appliance (ASA) Software |
Affected:
9.12.4.39
Affected: 9.12.4.40 Affected: 9.14.4.6 Affected: 9.14.4.7 Affected: 9.12.4.41 Affected: 9.12.4.47 Affected: 9.14.4.12 Affected: 9.12.4.48 Affected: 9.14.4.13 Affected: 9.12.4.50 Affected: 9.14.4.14 Affected: 9.12.4.52 Affected: 9.14.4.15 Affected: 9.12.4.54 Affected: 9.14.4.17 Affected: 9.12.4.55 Affected: 9.14.4.22 Affected: 9.14.4.23 Affected: 9.12.4.56 Affected: 9.12.4.58 Affected: 9.12.4.62 Affected: 9.12.4.65 Affected: 9.12.4.67 Affected: 9.14.4.24 |
guessed | |
| Cisco | Cisco Firepower Threat Defense Software |
Affected:
6.6.5.2
Affected: 6.4.0.15 Affected: 6.6.7 Affected: 6.4.0.16 Affected: 6.6.7.1 Affected: 6.4.0.17 Affected: 6.6.7.2 Affected: 6.4.0.18 |
guessed |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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