CVE-2020-3259

CRITICALNVD 7.59.0
EchelonGraph scoreHIGH confidence

“▲” beside the score: it is higher than NVD's CVSS score.

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2024-02-15), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 7.5 retained for reference. The 9.0 is the floor for confirmed exploitation, not an impact rating: this CVE's impact severity (EG Severity) is CVSS 7.5 HIGH under GitHub Security Advisory CVSS. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: CISA Known Exploited Vulnerabilities catalog, EPSS, GitHub Security Advisory, NVD CVSS v3
Exploited in the wild

Also known asEUVD-2020-24530 (ENISA EUVD) · GHSA-vw99-pf8w-g3cw (GitHub Security Advisories)Source: ENISA EUVD

9.0EG
EchelonGraph verdictMitigate nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV) — the reason this is sooner than the SSVC decision on this page at low or medium mission impact
CISA-KEV: ExploitedEPSS PROB: 72%CVSS: 7.5Exploit: No code on recordExposed services: Not assessed

No fix has been recorded since the CVE record was published in 2020 — use a compensating control (WAF / firewall / segmentation) and check the vendor's advisory.

CISA-ADP, in the CVE record, lists cisco firepower_threat_defense versions 6.2.3 up to but not including 6.2.3.16, 6.3.0 up to but not including 6.3.0.6, 6.4.0 up to but not including 6.4.0.9 and 6.5.0 up to but not including 6.5.0.5; cisco adaptive_security_appliance_software versions 9.8 up to but not including 9.8.4.20, 9.9 up to but not including 9.9.2..67, 9.10 up to but not including 9.10.1.40 and 9.12 up to but not including 9.12.3.9 as affected. No release containing a fix is confirmed on record.

A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to retrieve memory contents on an affected device, which could lead to the disclosure of confidential information. The vulnerability is due to a buffer tracking issue when the software parses invalid URLs that are requested from the web services interface. An attacker could exploit this vulnerability by sending a crafted GET request to the web services interface. A successful exploit could allow the attacker to retrieve memory contents, which could lead to the disclosure of confidential information. Note: This vulnerability affects only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section.

CVSS v3
7.5
EG Score
9.0CRITICALhigh confidence
EG Risk
89
EG Risk 89/100

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.
Exploitation100% × 40%
Fixed at 100% for a CISA KEV listing: EchelonGraph's rule.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Attend at low or medium mission impact; Act at high (mission-essential systems).
Exploitation active (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (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 has been recorded since the CVE record was published in 2020. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation sooner than your normal schedule at low or medium mission impact and as soon as possible at high.
EPSS PROB
72%
EPSS %ILE
99th
KEV
⚠ Exploited

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is the CISA KEV floor for confirmed exploitation, not an impact rating: its impact severity (EG Severity) is CVSS 7.5 HIGH.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
72% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-12). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
CISA KEV and EG-KEV Tier 1 (exploited in the wild)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Attend at medium mission impactAttend at low or medium mission impact; Act at high (mission-essential systems).CISA BOD 26-04: 3 days if the affected system is publicly exposed; 14 days if it is not.No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: this CVE is in CISA's KEV catalog, and CISA's required action for it, quoted below, applies whether or not a fix is released.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Attend at low or medium mission impact; Act at high (mission-essential systems).

No fix has been recorded since the CVE record was published in 2020. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation sooner than your normal schedule at low or medium mission impact and as soon as possible at high.

Exploitation active (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (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)3 days if the affected system is publicly exposed; 14 days if it is not.

No released fix is confirmed on this page, but CISA's timeline does not wait for a fix's release: this CVE is in CISA's KEV catalog, and CISA's required action for it, quoted below, applies whether or not a fix is released.

The score's inputs: In CISA KEV yes (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (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

CISA required action“Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.”

Quoted verbatim from CISA's Known Exploited Vulnerabilities catalog. CISA directs it at US federal civilian executive branch agencies under Binding Operational Directive (BOD) 26-04, which replaced BOD 22-01 on 10 June 2026; it is not EchelonGraph's advice. CISA's notes: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-info-disclose-9eJtycMB · https://nvd.nist.gov/vuln/detail/CVE-2020-3259

Published

May 6, 2020

Last Modified

August 12, 2026

Advisory Details (2)

Auto-updated Nov 13, 2026
⚠️ Actively exploited (CISA KEV, CISA Vulnrichment). No fix on record since 2020. Sources: cisa.
CISA🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-3259
Web page

Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Information Disclosure Vulnerability

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-info-disclose-9eJtycMB

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 10× in last 7d / 51× 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 its CVE.org record (CNA or CISA ADP). 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). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

Showing the most recent 100 of 1,111 rows 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. None are among the latest 100 rows. The 1,011 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-12 19:37 UTCEchelonGraph re-scored
  2. 2026-11-12 19:37 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  3. 2026-11-11 21:59 UTCEchelonGraph re-scored
  4. 2026-11-11 21:59 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  5. 2026-11-11 16:31 UTCEPSS rescoreEPSS 72% · 99th percentile
  6. 2026-11-11 00:21 UTCEchelonGraph re-scored
  7. 2026-11-11 00:21 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  8. 2026-11-10 16:34 UTCEPSS rescoreEPSS 72% · 99th percentile
  9. 2026-11-10 02:42 UTCEchelonGraph re-scored
  10. 2026-11-10 02:42 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  11. 2026-11-09 05:04 UTCEchelonGraph re-scored
  12. 2026-11-09 05:04 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  13. 2026-11-08 07:26 UTCEchelonGraph re-scored
  14. 2026-11-08 07:26 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  15. 2026-11-07 16:33 UTCEPSS rescoreEPSS 72% · 99th percentile
  16. 2026-11-07 09:48 UTCEchelonGraph re-scored
  17. 2026-11-07 09:48 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  18. 2026-11-06 12:10 UTCEchelonGraph re-scored
  19. 2026-11-06 12:10 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  20. 2026-11-05 16:30 UTCEPSS rescoreEPSS 72% · 99th percentile
  21. 2026-11-05 14:32 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  22. 2026-11-04 16:54 UTCEchelonGraph re-scored
  23. 2026-11-04 16:54 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  24. 2026-11-04 16:29 UTCEPSS rescoreEPSS 72% · 99th percentile
  25. 2026-11-03 19:15 UTCEchelonGraph re-scored
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  1. 2026-11-03 19:15 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  2. 2026-11-03 16:36 UTCEPSS rescoreEPSS 72% · 99th percentile
  3. 2026-11-02 21:32 UTCEchelonGraph re-scored
  4. 2026-11-02 21:32 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  5. 2026-11-01 23:52 UTCEchelonGraph re-scored
  6. 2026-11-01 23:52 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub severity MODERATE · GitHub CVSS 7.5
  7. 2026-11-01 02:14 UTCEchelonGraph re-scored
  8. 2026-11-01 02:14 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  9. 2026-10-31 16:28 UTCEPSS rescoreEPSS 72% · 99th percentile
  10. 2026-10-31 04:36 UTCEchelonGraph re-scored
  11. 2026-10-31 04:36 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  12. 2026-10-30 16:29 UTCEPSS rescoreEPSS 72% · 99th percentile
  13. 2026-10-30 06:58 UTCEchelonGraph re-scored
  14. 2026-10-30 06:58 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  15. 2026-10-29 09:20 UTCEchelonGraph re-scored
  16. 2026-10-29 09:20 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  17. 2026-10-28 16:28 UTCEPSS rescoreEPSS 72% · 99th percentile
  18. 2026-10-28 11:43 UTCEchelonGraph re-scored
  19. 2026-10-28 11:42 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  20. 2026-10-27 16:28 UTCEPSS rescoreEPSS 72% · 99th percentile
  21. 2026-10-27 14:04 UTCEchelonGraph re-scored
  22. 2026-10-27 14:04 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  23. 2026-10-26 16:27 UTCEPSS rescoreEPSS 72% · 99th percentile
  24. 2026-10-26 16:24 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  25. 2026-10-25 18:45 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  26. 2026-10-25 18:44 UTCEchelonGraph re-scored
  27. 2026-10-25 16:28 UTCEPSS rescoreEPSS 72% · 99th percentile
  28. 2026-10-24 21:06 UTCEchelonGraph re-scored
  29. 2026-10-24 21:06 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  30. 2026-10-23 23:27 UTCEchelonGraph re-scored
  31. 2026-10-23 23:27 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  32. 2026-10-23 16:28 UTCEPSS rescoreEPSS 72% · 99th percentile
  33. 2026-10-23 01:50 UTCEchelonGraph re-scored
  34. 2026-10-23 01:50 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  35. 2026-10-22 04:11 UTCEchelonGraph re-scored
  36. 2026-10-22 04:10 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  37. 2026-10-21 16:28 UTCEPSS rescoreEPSS 72% · 99th percentile
  38. 2026-10-21 06:32 UTCEchelonGraph re-scored
  39. 2026-10-21 06:31 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  40. 2026-10-20 16:28 UTCEPSS rescoreEPSS 72% · 99th percentile
  41. 2026-10-20 08:52 UTCEchelonGraph re-scored
  42. 2026-10-20 08:52 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  43. 2026-10-19 16:27 UTCEPSS rescoreEPSS 72% · 99th percentile
  44. 2026-10-19 11:14 UTCEchelonGraph re-scored
  45. 2026-10-19 11:14 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  46. 2026-10-18 13:36 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  47. 2026-10-18 09:24 UTCEchelonGraph re-scored
  48. 2026-10-17 15:58 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  49. 2026-10-16 18:18 UTCEchelonGraph re-scored
  50. 2026-10-16 18:18 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  51. 2026-10-16 16:33 UTCEPSS rescoreEPSS 72% · 99th percentile
  52. 2026-10-15 20:38 UTCEchelonGraph re-scored
  53. 2026-10-15 20:38 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  54. 2026-10-14 22:59 UTCEchelonGraph re-scored
  55. 2026-10-14 22:58 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  56. 2026-10-14 16:28 UTCEPSS rescoreEPSS 72% · 99th percentile
  57. 2026-10-14 01:18 UTCEchelonGraph re-scored
  58. 2026-10-14 01:18 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  59. 2026-10-13 16:28 UTCEPSS rescoreEPSS 72% · 99th percentile
  60. 2026-10-13 03:39 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  61. 2026-10-12 19:37 UTCEchelonGraph re-scored
  62. 2026-10-12 06:01 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  63. 2026-10-12 02:03 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  64. 2026-10-11 22:08 UTCEchelonGraph re-scored
  65. 2026-10-11 22:08 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  66. 2026-10-11 18:11 UTCEchelonGraph re-scored
  67. 2026-10-11 18:10 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
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  69. 2026-10-11 14:14 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  70. 2026-10-11 13:43 UTCEPSS rescoreEPSS 72% · 99th percentile
  71. 2026-10-11 10:19 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  72. 2026-10-11 06:24 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  73. 2026-10-11 02:29 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5
  74. 2026-10-10 22:32 UTCEchelonGraph re-scored
  75. 2026-10-10 22:32 UTCGHSA enrichmentGHSA-vw99-pf8w-g3cw · GitHub CVSS 7.5

Frequently asked(6)

What is CVE-2020-3259?
CVE-2020-3259 is a critical-severity vulnerability; its CVE record was published on May 6, 2020. A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to retrieve memory contents on an affected device, which could lead to the disclosure of confidential…
When was CVE-2020-3259 made public?
CVE-2020-3259 was made public on May 6, 2020: that is the date its CVE record's CNA, Cisco Systems, Inc., gives for when the vulnerability was made public. The CVE record itself was published on May 6, 2020. EchelonGraph's copy of the record carries a last-modified date of August 12, 2026; the record at its source may have been updated since.
Is CVE-2020-3259 actively exploited?
Yes. CISA added CVE-2020-3259 to the Known Exploited Vulnerabilities catalog on February 15, 2024, affecting Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD). KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate attention. No fix has been recorded since the CVE record was published in 2020. Check the vendor's advisory for a fixed release; until one is applied, restrict network exposure of the affected system or apply the vendor's mitigation.
What is the CVSS score of CVE-2020-3259?
CVE-2020-3259 has a CVSS v3 base score of 7.5 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0 (CRITICAL).
Which products are affected by CVE-2020-3259?
CVE-2020-3259 affects Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD).
How do I remediate CVE-2020-3259?
No fix for CVE-2020-3259 has been recorded since its CVE record was published in 2020. Restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and check the vendor's advisory for a fix. CISA-ADP, in the CVE record, lists cisco firepower_threat_defense versions 6.2.3 up to but not including 6.2.3.16, 6.3.0 up to but not including 6.3.0.6, 6.4.0 up to but not including 6.4.0.9 and 6.5.0 up to but not including 6.5.0.5; cisco adaptive_security_appliance_software versions 9.8 up to but not including 9.8.4.20, 9.9 up to but not including 9.9.2..67, 9.10 up to but not including 9.10.1.40 and 9.12 up to but not including 9.12.3.9 as affected. No release containing a fix is confirmed on record.

Dependency Blast Radius

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