# Cisco ASA and FTD Information Disclosure · pwn.watch

> 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. Added to the CISA KEV catalog on 2024-02-15. CISA lists known use in ransomware campaigns. CVE-2020-3259 was assigned before 2024; the KEV listing came in 2024.

Page: https://pwn.watch/i/cisco-adaptive-security-appliance-asa-and-firepowe-cve-2020-3259 · generated 2026-10-23T00:16:28.879Z

## Status
- Severity: high · status: closed · patch: patched
- Product: Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD)
- Started: 2024-02-15 · closed: 2024-02-15
- CVEs: CVE-2020-3259
- Affected: See vendor advisory (versions are not listed in the KEV record)
- Fixed in: See vendor advisory linked in sources

## Follow this incident
- RSS (one item per update): https://pwn.watch/i/cisco-adaptive-security-appliance-asa-and-firepowe-cve-2020-3259/feed.xml
- JSON Feed: https://pwn.watch/i/cisco-adaptive-security-appliance-asa-and-firepowe-cve-2020-3259/feed.json
- Full data (timeline, sources, posts, agentBrief): https://pwn.watch/i/cisco-adaptive-security-appliance-asa-and-firepowe-cve-2020-3259.json
- This file: https://pwn.watch/i/cisco-adaptive-security-appliance-asa-and-firepowe-cve-2020-3259/llms.txt

## Updates (newest first)
- 2024-02-15: CISA added CVE-2020-3259 to the KEV catalog (federal deadline 2024-03-07) (https://www.cisa.gov/known-exploited-vulnerabilities-catalog)

## Fix brief
# Security brief: Cisco ASA and FTD Information Disclosure

Source: https://pwn.watch/i/cisco-adaptive-security-appliance-asa-and-firepowe-cve-2020-3259 · status: closed (closed Feb 15, 2024) · severity: high · updated Feb 15, 2024

## Patch status
**PATCHED: fixed releases exist. Upgrade to a fixed version.**

## What it is
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. Added to the CISA KEV catalog on 2024-02-15. CISA lists known use in ransomware campaigns. CVE-2020-3259 was assigned before 2024; the KEV listing came in 2024.

Severity detail: CVSS 7.5 (v3.0, CNA), actively exploited (CISA KEV); known ransomware use

- Product: Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD)
- CVE / advisory ids: CVE-2020-3259

## Affected versions
- See vendor advisory (versions are not listed in the KEV record)

## Check whether you're affected
No generic command applies (the product is a hosted service, appliance or desktop app). Check the installed version in its admin UI / About screen and compare with the versions above.

## Fix
Upgrade to one of these fixed versions (or later on the same branch):
- See vendor advisory linked in sources

After upgrading, re-run the checks above and redeploy/restart the affected services.

## Latest updates
- Feb 15, 2024: CISA added CVE-2020-3259 to the KEV catalog (federal deadline 2024-03-07)

## Advisories
- [Cisco advisory: CVE-2020-3259](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-info-disclose-9eJtycMB) (Cisco)
- [NVD: CVE-2020-3259](https://nvd.nist.gov/vuln/detail/CVE-2020-3259) (NVD)
- [CISA Known Exploited Vulnerabilities Catalog](https://www.cisa.gov/known-exploited-vulnerabilities-catalog) (CISA)

## Caveats
Derived from the CISA KEV JSON feed (catalogVersion 2026.10.21); CVSS from the CVE record (cveawg.mitre.org). startedAt is the CVE publication date when it fell in 2024 before the KEV listing, else the KEV dateAdded; exploitation may have begun earlier. closedAt is the KEV listing date (a fix or mitigation was available then unless noted).

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Machine-readable: https://pwn.watch/i/cisco-adaptive-security-appliance-asa-and-firepowe-cve-2020-3259.json · all incidents: https://pwn.watch/incidents.json. Verify against the vendor advisory before changing production systems.