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Content Security Management ApplianceApplication · Cisco

CVE-2021-1516

MEDIUM · 6.5 CVSS v3.1 Published 2021-05-06
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A vulnerability in the web-based management interface of Cisco AsyncOS Software for Cisco Content Security Management Appliance (SMA), Cisco Email Security Appliance (ESA), and Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to access sensitive information on an affected device. The vulnerability exists because confidential information is included in HTTP requests that are exchanged between the user and the device. An attacker could exploit this vulnerability by looking at the raw HTTP requests that are sent to the interface. A successful exploit could allow the attacker to obtain some of the passwords that are configured throughout the interface.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

This is an information disclosure vulnerability in Cisco's AsyncOS web-based management interface for Content Security Management Appliance (SMA), Email Security Appliance (ESA), and Web Security Appliance (WSA). Confidential information, including passwords, is transmitted in plaintext within HTTP requests exchanged between users and the device. An authenticated attacker can capture these HTTP requests and extract stored credentials.

MitigationApply the vendor-supplied patch or update to Cisco AsyncOS Software. Until patched, monitor HTTP traffic to the management interface and ensure only authorized administrators have access.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Content Security Management ApplianceApplication
Affected:all versions
Email Security ApplianceApplication
Affected:all versions
Web Security ApplianceApplication
Affected:all versions
Ironport Web Security ApplianceApplication
Affected:= 13.6.2-023= 14.0.0-090= 14.0.0-133= 14.0.0-292= 14.0.0-300

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the installed appliance type
    Access the device CLI or web interface and determine if the device is a Cisco Content Security Management Appliance (SMA), Email Security Appliance (ESA), or Web Security Appliance (WSA). Check the product model and firmware version displayed in the management interface or via CLI command 'version'.
    Affected if The device is a Cisco SMA, ESA, or WSA (including Ironport WSA models).
  2. Verify web-based management interface is enabled
    Log into the device CLI or web UI and confirm the AsyncOS web-based management interface is actively running. In the web UI, this is typically accessible at the default management URL. In CLI, use 'admin' or check network configuration.
    Affected if The web-based management interface is enabled and accessible.
  3. Check management interface protocol
    Examine the URL used to access the management interface. Look at whether the connection uses HTTP (port 80) or HTTPS (port 443). Check the device network configuration via CLI with 'iphttp' or 'iphttps' commands, or inspect the browser address bar when accessing the management interface.
    Affected if HTTP (not HTTPS) is used to access the web-based management interface, as plaintext transmission of credentials occurs over HTTP.
  4. Review HTTP traffic to management interface
    Use a network packet capture tool (such as tcpdump or Wireshark) on network segments carrying traffic to the management interface. Filter for HTTP traffic to the appliance IP on port 80. Examine if sensitive data including passwords are transmitted in plaintext within request bodies or URLs.
    Affected if HTTP traffic to the management interface contains plaintext passwords or other confidential information in request payloads.

A user is affected if they are running a Cisco SMA, ESA, or WSA with the AsyncOS web-based management interface enabled and accessible over HTTP instead of HTTPS.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the vendor-supplied patch or update to Cisco AsyncOS Software. Until patched, monitor HTTP traffic to the management interface and ensure only authorized administrators have access.

Fix this in Content Security Management Appliance Scoped from the published advisory
  • Consultation4.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,180
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Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-1516 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data