CVE-2021-1445Network attack vector

Device reload via unvalidated HTTPS request

Published Apr 29, 2021 · Updated Nov 8, 2024

Out-of-bounds write in Cisco Adaptive Security Appliance Software allows remote attackers to reload devices via crafted HTTPS requests. The Web Services VPN request handler does not properly validate the HTTPS request before an out-of-bounds memory write occurs. Exposure requires a vulnerable release configured to terminate AnyConnect IKEv2 client-services or SSL VPN connections; successful exploitation reloads the device and interrupts service.

CVSS severity8.6
High
EPSS probability1.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds write in Cisco Adaptive Security Appliance Software allows remote attackers to reload devices via crafted HTTPS requests. The Web Services VPN request handler does not properly validate the HTTPS request before an out-of-bounds memory write occurs. Exposure requires a vulnerable release configured to terminate AnyConnect IKEv2 client-services or SSL VPN connections; successful exploitation reloads the device and interrupts service.

The record

CVE
CVE-2021-1445
Published
Apr 29, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco Adaptive Security Appliance (ASA) Software
Classifications
CWE-787, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Adaptive Security Appliance (ASA) Softwareversion=n/a

Published CVSS scores

8.6Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:X
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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