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.
CVE-2022-20866
“—” beside the score: it is equal to NVD's CVSS score.
Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2022-08-11. NVD baseline CVSS 7.5; sources differ by 0.0.
- High severity, but no confirmed exploitation yet
No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.
- CVSS v3
- 7.5
- EG Score
- 7.5HIGHmedium confidence
- EG Risk
- 50EG Risk 50/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity75% × 45%Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation40% × 40%EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines, and watch the vendor's advisory for the fix. - EPSS PROB
- 18%
- EPSS %ILE
- 97th
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 18% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-20). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines, and watch the vendor's advisory for the fix.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
August 10, 2022
Last Modified
August 11, 2026
Advisory Details (1)
Auto-updated Aug 11, 2026Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software RSA Private Key Leak Vulnerability
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-rsa-key-leak-Ms7UEfZzWeakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 10× in last 7d / 32× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
Showing the most recent 94 of 172 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 6 repeat rows among the latest 100 are merged into the row they repeat. The 78 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-10-23 16:28 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-22 16:29 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-21 16:28 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-21 08:08 UTCEG score recompute
- 2026-10-21 08:08 UTCGHSA enrichmentGHSA-96q7-c2w2-93p8 · GitHub severity HIGH · GitHub CVSS 7.5
- 2026-10-20 16:28 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-19 16:28 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-18 16:28 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-18 08:45 UTCEG score recompute
- 2026-10-17 16:29 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-16 16:34 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-15 16:28 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-14 16:29 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-13 16:28 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-12 19:02 UTCEG score recompute
- 2026-10-12 16:30 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-11 23:28 UTCEG score recompute
- 2026-10-11 13:44 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-10 19:56 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-09 20:04 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-08 16:40 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-07 23:45 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-06 15:14 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-04 23:19 UTCEPSS rescoreEPSS 18% · 97th percentile
- 2026-10-03 14:22 UTCEPSS rescoreEPSS 17% · 97th percentile
Show 69 moreShow fewer
- 2026-10-02 16:23 UTCEPSS rescoreEPSS 17% · 97th percentile
- 2026-09-30 15:48 UTCEG score recompute
- 2026-09-30 15:00 UTCEPSS rescoreEPSS 17% · 97th percentile
- 2026-09-29 15:15 UTCEPSS rescoreEPSS 17% · 97th percentile
- 2026-09-26 15:54 UTCEPSS rescoreEPSS 17% · 97th percentile
- 2026-09-26 00:21 UTCEPSS rescoreEPSS 17% · 97th percentile
- 2026-09-24 14:00 UTCEPSS rescoreEPSS 17% · 97th percentile
- 2026-09-23 13:45 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-22 14:44 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-21 20:28 UTCEPSS rescoreEPSS 17% · 97th percentile
- 2026-09-19 15:38 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-18 19:24 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-17 19:23 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-16 14:05 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-15 03:06 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-12 14:57 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-11 14:49 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-11 09:33 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-08 21:57 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-07 15:58 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-06 13:45 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-05 15:25 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-04 13:57 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-04 05:03 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-02 14:09 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-09-01 13:51 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-30 19:14 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-30 01:19 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-28 21:38 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-27 14:22 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-26 14:43 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-25 13:46 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-24 14:13 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-21 23:46 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-20 22:52 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-19 17:01 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-18 13:45 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-17 13:44 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-16 14:53 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-16 02:11 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-15 01:27 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-13 21:57 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-12 13:48 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-11 19:58 UTCEG score recompute
- 2026-08-11 19:58 UTCGHSA enrichmentGHSA-96q7-c2w2-93p8 · GitHub severity HIGH · GitHub CVSS 7.5
- 2026-08-11 19:37 UTCNVD updateCVSS v3 → 7.5
- 2026-08-11 13:38 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-08 16:34 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-07 16:24 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-06 13:44 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-05 19:15 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-04 15:06 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-03 10:33 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-02 02:24 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-08-01 04:13 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-30 16:25 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-28 15:33 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-26 14:52 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-25 14:15 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-24 14:15 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-23 14:16 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-23 02:07 UTCEG score recompute
- 2026-07-22 22:54 UTCEG score recompute
- 2026-07-22 14:06 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-21 15:22 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-20 17:05 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-19 02:27 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-18 10:02 UTCEPSS rescoreEPSS 17% · 96th percentile
- 2026-07-16 17:00 UTCEPSS rescoreEPSS 17% · 96th percentile
Public detection checks
(1 reference)A public detection check is referenced for this CVE (1 GitHub checker repository). A GitHub repository named or described as a checker or scanner checks whether a system is affected; it is not necessarily exploit code.
- GitHub checkerCiscoPSIRT/CVE-2022-20866Published Jul 13, 2022
RSA Key Checker for CVE-2022-20866
Open source ↗
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2022-20866?
When was CVE-2022-20866 made public?
Is CVE-2022-20866 actively exploited?
What is the CVSS score of CVE-2022-20866?
How do I remediate CVE-2022-20866?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2022-20866
Is Your Infrastructure Affected by CVE-2022-20866?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.