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NVD / CVE Program· CNA cisco

CVE-2020-3259: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Information Disclosure Vulnerability

HighCVSS 7.5 · v3.1KEVWeaponized No fix recorded

Noroxi assessment

Priority: Now (action score 81/100)

  • CISA has confirmed exploitation in the wild (Feb 15, 2024); it is known to be used in ransomware campaigns. Remediation deadline for US federal agencies: Mar 7, 2024.
  • Probability of exploitation in the next 30 days: 71.5% (FIRST EPSS); higher than 99.4% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • According to the record, no fixed version is available yet.

Patch today or shut off access. Until a fix is released, restrict access to the affected component and follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · CISA KEV · FIRST EPSS

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.

Published
May 6, 2020
Updated
Aug 12, 2026
EPSS
71.5% · 99th percentile

Report tools

JSON

Action score

81

Now

Patch today or shut off access.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
30 / 30 · Listed
EPSS
21 / 30 · 71.5%

CISA SSVC decision

Exploitation
active
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
7.5
CNA · cisco
7.5
agree

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on Feb 15, 2024. That signals real attacks, not theory.

Remediation deadline for US federal agencies: Mar 7, 2024.

Known to be used in ransomware campaigns.

Get told when this record changes

  • In CISA KEV: exploitation in the wild confirmed
  • Weaponized exploit exists
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2020-3259

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
ciscosecure firewall threat defense
ciscoadaptive security appliance software

Versions reported by the vendor

Affected version ranges reported by the assigning authority (cisco). Independent of NVD's CPE analysis and usually ahead of it.

  • Cisco Cisco Adaptive Security Appliance (ASA) Software

    • n/aaffected
Affected versions · NVD (5)

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • cisco adaptive security appliance software9.8 and later · before 9.8.4.20
  • cisco adaptive security appliance software9.9 and later · before 9.9.2.67
  • cisco adaptive security appliance software9.10 and later · before 9.10.1.40
  • cisco adaptive security appliance software9.12 and later · before 9.12.3.9
  • cisco adaptive security appliance software9.13 and later · before 9.13.1.10

Same product

cisco: all records

Other highest-scoring records for the same primary product.

  • CVE-2020-3580Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Interface Cross-Site Scripting…KEV
    80Now
  • CVE-2020-3187Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Path Traversal Vulnerability
    65This week
  • CVE-2024-20481A vulnerability in the Remote Access VPN (RAVPN) service of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat…KEV
    60This week

Published before and after this one in the same product

  • ← EarlierCVE-2020-3254May 6, 2020 · Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Media Gateway Control Protocol Denial of Service Vulnerabilities
    31Monitor
  • ← EarlierCVE-2020-3255May 6, 2020 · Cisco Firepower Threat Defense Software Packet Flood Denial of Service Vulnerability
    31Monitor
  • Later →CVE-2020-3283May 6, 2020 · Cisco Firepower 1000 Series SSL/TLS Denial of Service Vulnerability
    35Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. CISA KEV+1379 d
  3. TodayNov 13, 2026+2382 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Not on record for this CVE: patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
none
Availability
none
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
None
Availability impact
None

Weakness class (CWE)

CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

nvd-primary

Root cause

The extension requests broader permissions than its function needs and sends the data it collects out for purposes beyond its stated function.

The bug in code

The whole CWE-200 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

json
{  "permissions": ["tabs", "<all_urls>"],  "background": { "service_worker": "analytics.js" }}

Fixed

json
{  "permissions": ["activeTab"],  "host_permissions": ["https://yildiz.example/*"]}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records