CVE-2020-3259: Cisco ASA and FTD Information Disclosure Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 15 Feb 2024, 1,380 days after the CVE record was published.
- How likely is exploitation in the next 30 days?
- 71.5%
EPSS score, percentile 99.4 of all scored records
- How severe?
- 7.5 High
CVSS v3.0 base score, given by the CNA
- What should I do?
Required action (CISA), due 7 Mar 2024: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Which versions are affected?
Affected: unspecified
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
What to do
Required action, set by CISA
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
CISA due date for this action: 7 March 2024.
Advisories and patches
Linked from CISA's catalog entry
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-info-disclose-9eJtycMB
- https://nvd.nist.gov/vuln/detail/CVE-2020-3259
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | unspecified |
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
About this vulnerability
Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) contain an information disclosure vulnerability. An attacker could retrieve memory contents on an affected device, which could lead to the disclosure of confidential information due to a buffer tracking issue when the software parses invalid URLs that are requested from the web services interface. This vulnerability affects only specific AnyConnect and WebVPN configurations.
Summary: CISA's KEV catalog, as of 28 Oct 2026.
- CISA added CVE-2020-3259 to its Known Exploited Vulnerabilities (KEV) catalog on 15 Feb 2024.
- CISA marks it as known to be used in ransomware campaigns.
- The due date CISA sets for the required action is 7 Mar 2024.
- The CVE record was published on 6 May 2020, 1,380 days before it was added to KEV.
- The CVE record carries a CVSS v3.0 base score of 7.5 (High), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 71.5% (percentile 99.4), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact partial.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.
Description
Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Information Disclosure Vulnerability
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.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
Weakness
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| 6 May 2020 | CVE record published |
| 15 Feb 2024 | Added to CISA KEV |
| 7 Mar 2024 | CISA due date for the required action |
| 12 Aug 2026 | CVE record last updated |
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