Security readout for executives and security teams
Plain-English summary
Affected Cisco ASA and FTD appliances can expose fragments of device memory to an unauthenticated internet attacker. Those fragments may contain confidential information. Risk is limited to specific AnyConnect and WebVPN configurations, but confirmed exploitation makes exposed devices an urgent concern.
Executive priority
Treat confirmed affected, externally reachable devices as a high-priority remediation item. Accelerate inventory and vendor-guided updating because exploitation is documented and successful attacks may disclose sensitive memory without authentication or user interaction.
Technical view
A buffer-tracking flaw in the ASA and FTD web services interface mishandles invalid URLs. A remote, unauthenticated attacker can trigger memory disclosure through a crafted web request. CVSS 3.0 rates it 7.5: network-accessible, low complexity, no privileges or user interaction, with high confidentiality impact.
Likely exposure
Exposure requires affected Cisco ASA or FTD software with specific AnyConnect or WebVPN configurations and an accessible web services interface. The supplied evidence does not identify exact vulnerable versions, so inventory and configuration review against Cisco’s advisory are necessary.
Exploitation context
CISA lists CVE-2020-3259 in its Known Exploited Vulnerabilities catalog, supporting confirmed exploitation in the wild. The supplied sources do not describe exploitation scale, targeted organizations, disclosed data, or attribution.
Researcher notes
CWE-200 and the CVSS vector indicate confidentiality-only impact in the documented vulnerability; integrity and availability impacts are not established. Exact affected releases, fixes, indicators, and exploitation prevalence are absent from the supplied bundle and should be obtained from Cisco and CISA guidance.
Mitigation direction
- Identify ASA and FTD devices using AnyConnect or WebVPN.
- Compare software versions and configurations with Cisco’s vulnerable-products guidance.
- Apply the vendor-specified fixed software release or mitigation.
- Restrict unnecessary access to affected web services while remediation is pending.
- Review potentially exposed devices for signs of compromise.
Validation and detection
- Inventory internet-facing and internally reachable ASA and FTD web services.
- Confirm whether each device uses an affected AnyConnect or WebVPN configuration.
- Verify installed releases against Cisco’s advisory and fixed-release information.
- Confirm remediation through version and configuration review.
- Examine relevant security telemetry for suspicious requests and possible memory disclosure activity.
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
SSVC decision data
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:N3.93.6ciscoVulnerability 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
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- Added to KEVCISA-ADP
CISA Known Exploited Vulnerabilities metadata lists this CVE as known exploited.
- ADP timelineCISA-ADP
CVE-2020-3259 added to CISA KEV
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
- 2024-02-15T00:00:00.000Z: CVE-2020-3259 added to CISA KEV
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, cisco · vendor-advisory, x_refsource_CISCO
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-3259CVE reference, CISA-ADP · 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.