NVD / CVE Program· CNA cisco

CVE-2022-20866: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software RSA Private Key Leak Vulnerability

Noroxi assessment

Priority: Monitor (action score 35/100)

Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
Probability of exploitation in the next 30 days: 18.1% (FIRST EPSS); higher than 97.2% of all records.
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.
According to the record, no fixed version is available yet.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A vulnerability in the handling of RSA keys on devices running Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to retrieve an RSA private key. This vulnerability is due to a logic error when the RSA key is stored in memory on a hardware platform that performs hardware-based cryptography. An attacker could exploit this vulnerability by using a Lenstra side-channel attack against the targeted device. A successful exploit could allow the attacker to retrieve the RSA private key. The following conditions may be observed on an affected device: This vulnerability will apply to approximately 5 percent of the RSA keys on a device that is running a vulnerable release of Cisco ASA Software or Cisco FTD Software; not all RSA keys are expected to be affected due to mathematical calculations applied to the RSA key. The RSA key could be valid but have specific characteristics that make it vulnerable to the potential leak of the RSA private key. If an attacker obtains the RSA private key, they could use the key to impersonate a device that is running Cisco ASA Software or Cisco FTD Software or to decrypt the device traffic. See the Indicators of Compromise section for more information on the detection of this type of RSA key. The RSA key could be malformed and invalid. A malformed RSA key is not functional, and a TLS client connection to a device that is running Cisco ASA Software or Cisco FTD Software that uses the malformed RSA key will result in a TLS signature failure, which means a vulnerable software release created an invalid RSA signature that failed verification. If an attacker obtains the RSA private key, they could use the key to impersonate a device that is running Cisco ASA Software or Cisco FTD Software or to decrypt the device traffic.

HighCVSS 7.5 · v3.1—Proof of concept No fix recorded

Pre-auth

BDU:2022-04941

Published: Aug 10, 2022
Updated: Aug 11, 2026
EPSS: 18.1% · 97th percentile
CWE: CWE-203

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 30 / 40 · 7.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 5 / 30 · 18.1%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: 7.5
CNA · cisco: 7.4; 0.1 point gap

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
Proof of concept exists, no weaponized module
No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

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 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
cisco	firepower 1000	cpe:2.3:h:cisco:firepower_1000
cisco	firepower 1010	cpe:2.3:h:cisco:firepower_1010
cisco	firepower 1020	cpe:2.3:h:cisco:firepower_1020
cisco	firepower 1030	cpe:2.3:h:cisco:firepower_1030
cisco	firepower 1040	cpe:2.3:h:cisco:firepower_1040

and 22 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 software9.16.0 and later · before 9.16.3.19
cisco adaptive security appliance software9.17.0 and later · before 9.17.1.13
cisco adaptive security appliance software9.18.0 and later · before 9.18.2

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 records

Other highest-scoring records for the same primary product.

CVE-2025-20333A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat DKEV
91Now
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 FTKEV
90Now
CVE-2020-3452Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Read-Only Path Traversal VulnerabilityKEV
90Now

Published before and after this one in the same product

← EarlierCVE-2020-3458Oct 21, 2020 · Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software for Firepower 1000/2100 Series Appliances Secure Boot Bypass Vulnerabilities
26Monitor
← EarlierCVE-2022-20737May 3, 2022 · Cisco Adaptive Security Appliance Software Clientless SSL VPN Heap Overflow Vulnerability
28Monitor
Later →CVE-2022-20826Nov 15, 2022 · A vulnerability in the secure boot implementation of Cisco Secure Firewalls 3100 Series that are running Cisco Adaptive Security Appliance (
27Monitor

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

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

Proof-of-concept repository on GitHub ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
Source	Kind	Date
Proof-of-concept repository on GitHub	stars:7	2022-07-13

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.

First PoCJul 13, 2022-29 d
PublishedAug 10, 2022
TodayNov 5, 2026+1548 d

EPSS, last 120 days

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 researchers

Finders, 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).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-22-0542 · Aug 11, 2022(Cisco Güvenlik Zafiyeti)

All national notices →

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-203 · Observable Discrepancy

CVSS 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.

Attack patterns (CAPEC)

Black Box Reverse EngineeringCAPEC-189Low

ATT&CK techniques

—

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-rsa-key-leak-Ms7UEfZz

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records