Security readout for executives and security teams
Plain-English summary
CVE-2020-3259 can let an unauthenticated remote attacker read memory contents from affected Cisco ASA or FTD devices. The disclosed memory could contain confidential information. Business urgency is high because these devices often sit at network edges and CISA lists the CVE in its Known Exploited Vulnerabilities catalog.
Executive priority
Treat this as a high-priority edge-device exposure issue. The vulnerability can disclose confidential memory contents without authentication, and CISA KEV status means delayed remediation carries heightened operational risk.
Technical view
The flaw is in the ASA and FTD web services interface. Invalid URL parsing can trigger a buffer tracking issue, allowing memory disclosure through a crafted GET request. The source bundle states this affects only specific AnyConnect and WebVPN configurations. CVSS is 7.5 with network attack vector and no required authentication.
Likely exposure
Exposure is most likely on Cisco ASA or FTD appliances with affected web services enabled for specific AnyConnect or WebVPN configurations. The source bundle does not provide affected version ranges, so teams must verify products and versions against Cisco’s advisory.
Exploitation context
CISA KEV inclusion supports that this vulnerability has been exploited in the wild. The provided sources describe unauthenticated remote memory disclosure, but do not provide safe evidence about current campaign volume, targeted sectors, or specific attacker tooling.
Researcher notes
The bundle confirms CWE-200, CVSS 7.5, unauthenticated remote reachability, and confidentiality impact only. Version and fixed-release details are not included in the bundle, so researchers should avoid assuming affected ranges without the Cisco advisory.
Mitigation direction
- Check Cisco’s advisory for affected versions and fixed releases.
- Upgrade affected ASA and FTD software according to Cisco guidance.
- Confirm whether AnyConnect or WebVPN configurations are present.
- Reduce external exposure of web services where operationally feasible.
- Prioritize remediation for internet-facing security appliances.
- Track CISA KEV requirements for applicable environments.
Validation and detection
- Inventory Cisco ASA and FTD appliances.
- Identify devices exposing web services externally.
- Verify AnyConnect and WebVPN configuration status.
- Compare installed versions against Cisco’s advisory.
- Review edge-device monitoring for suspicious web service requests.
- Document remediation status for KEV tracking.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-200: Information exposure and cloud metadata lookup
Information exposure and SSRF weaknesses can make discovery, cloud metadata, and credential material review relevant. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2020-3259 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.5 (3.0)
- Known Exploited
- Yes
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CISA KEV status
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
7.5HighVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- 20200506 Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Information Disclosure VulnerabilityCVE reference · vendor-advisory, x_refsource_CISCO
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-3259CVE reference · government-resource
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Exposure of Sensitive Information to an Unauthorized Actor
Exposure of Sensitive Information to an Unauthorized Actor represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.