Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Low-Entropy Keys Vulnerability
A vulnerability in the deterministic random bit generator (DRBG), also known as pseudorandom number generator (PRNG), in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software for Cisco ASA 5506-X, ASA 5508-X, and ASA 5516-X Firewalls could allow an unauthenticated, remote attacker to cause a cryptographic collision, enabling the attacker to discover the private key of an affected device. This vulnerability is due to insufficient entropy in the DRBG for the affected hardware platforms when generating cryptographic keys. An attacker could exploit this vulnerability by generating a large number of cryptographic keys on an affected device and looking for collisions with target devices. A successful exploit could allow the attacker to impersonate an affected target device or to decrypt traffic secured by an affected key that is sent to or from an affected target device.
- Published
- Mar 23, 2023
- Updated
- Aug 11, 2026
- EPSS
- 0.7% · 52th percentile
- CWE
- CWE-332
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Report tools
Action score
30
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.7%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 7.5
- CNA · cisco
- 5.3
- 2.2 point gap
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
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 | cpe:2.3:a:cisco:adaptive_security_appliance |
| cisco | secure firewall threat defense | cpe:2.3:a:cisco:secure_firewall_threat_defense |
| cisco | asa 5506-x | cpe:2.3:h:cisco:asa_5506-x |
| cisco | asa 5506h-x | cpe:2.3:h:cisco:asa_5506h-x |
| cisco | asa 5506w-x | cpe:2.3:h:cisco:asa_5506w-x |
| cisco | asa 5508-x | cpe:2.3:h:cisco:asa_5508-x |
| cisco | asa 5516-x | cpe:2.3:h:cisco:asa_5516-x |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cisco adaptive security appliancebefore 9.12.1
- cisco secure firewall threat defensebefore 6.4.0
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
- n/aaffected
Same product
cisco: all recordsOther highest-scoring records for the same primary product.
- CVE-2020-3572Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SSL/TLS Session Denial of Service Vulnerability35Monitor
- CVE-2020-3436Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services File Upload Denial of Service Vulnerability35Monitor
- CVE-2020-3304Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Denial of Service Vulnerability35Monitor
- CVE-2021-34793Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Transparent Mode Denial of Service Vulnerability34Monitor
- CVE-2013-3382The Next-Generation Firewall (aka NGFW, formerly CX Context-Aware Security) module 9.x before 9.1.1.9 and 9.1.2.x before 9.1.2.12 for Cisco 32Monitor
- CVE-2011-0395Cisco Adaptive Security Appliances (ASA) 5500 series devices with software 8.0 before 8.0(5.20), 8.1 before 8.1(2.48), 8.2 before 8.2(3), an32Monitor
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
- high · data can be read
- Integrity
- none
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- None
- Availability impact
- None
Weakness class (CWE)
CWE-332 · Insufficient Entropy in PRNGCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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.