CVE-2020-3308

mediumpriority · track · 20EPSS 0.006 · 49 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.61% (49th) EPSS

CVSS 4 · medium

Is it mine?

33 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

A vulnerability in the Image Signature Verification feature of Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker with administrator-level credentials to install a malicious software patch on an affected device. The vulnerability is due to improper verification of digital signatures for patch images. An attacker could exploit this vulnerability by crafting an unsigned software patch to bypass signature checks and loading it on an affected device. A successful exploit could allow the attacker to boot a malicious software patch image.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

No fix is available; mitigate or reduce exposure.

No fix available5.3.0cisco_csaf
No remediation is available at this time.
No fix available5.4.0cisco_csaf
No remediation is available at this time.
No fix available6.0.0cisco_csaf
No remediation is available at this time.
No fix available6.0.0.1cisco_csaf
No remediation is available at this time.
No fix available6.0.1cisco_csaf
No remediation is available at this time.
No fix available6.0.1.1cisco_csaf
No remediation is available at this time.
No fix available6.0.1.2cisco_csaf
No remediation is available at this time.
No fix available6.0.1.3cisco_csaf
No remediation is available at this time.
No fix available6.0.1.4cisco_csaf
No remediation is available at this time.
No fix available6.1.0cisco_csaf
No remediation is available at this time.
No fix available6.1.0.1cisco_csaf
No remediation is available at this time.
No fix available6.1.0.2cisco_csaf
No remediation is available at this time.
No fix available6.1.0.3cisco_csaf
No remediation is available at this time.
No fix available6.1.0.4cisco_csaf
No remediation is available at this time.
No fix available6.1.0.5cisco_csaf
No remediation is available at this time.
No fix available6.1.0.6cisco_csaf
No remediation is available at this time.
No fix available6.1.0.7cisco_csaf
No remediation is available at this time.
No fix available6.2.0cisco_csaf
No remediation is available at this time.
No fix available6.2.0.1cisco_csaf
No remediation is available at this time.
No fix available6.2.0.2cisco_csaf
No remediation is available at this time.
No fix available6.2.0.3cisco_csaf
No remediation is available at this time.
No fix available6.2.0.4cisco_csaf
No remediation is available at this time.
No fix available6.2.0.5cisco_csaf
No remediation is available at this time.
No fix available6.2.0.6cisco_csaf
No remediation is available at this time.
No fix available6.2.1cisco_csaf
No remediation is available at this time.
No fix available6.2.2cisco_csaf
No remediation is available at this time.

cvss

Technical severity, 0–10. One row per scoring source.

4.9

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04mediumAV:N/AC:L/Au:S/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8 · impact 2.9

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 1.2 · impact 3.6

v3.04.9mediumCVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:Nsecondary · ENISA EU

v3.04.9mediumCVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:Nsecondary · psirt@cisco.com USexploitability 1.2 · impact 3.6

v3.04.9mediumCVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:Nsecondary · Cisco PSIRT US

v3.14.9mediumAV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:Nsecondary · FSTEC (BDU) RU

v3.14.5mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-347USprimaryCWE-347US

affected products (33)

Products and version ranges known to be affected.

showing 20 of 33

advisories (1)

Vendor and ecosystem advisories describing this.

cisco-sa-sigbypass-FcvPPCePCisco Firepower Threat Defense Software Signature Verification Bypass Vulnerability2020-05-06csaf · cisco_csafUS
A vulnerability in the Image Signature Verification feature of Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker with administrator-level credentials to install a malicious software patch on an affected device. The vulnerability is due to improper verification of digital signatures for patch images. An attacker could exploit this vulnerability by crafting an unsigned software patch to bypass signature checks and loading it on an affected device. A successful exploit could allow the attacker to boot a malicious software patch image. Cisco has released software updates that address the vulnerability described in this advisory. There are no workarounds that address this vulnerability.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisco_csaf NVD CVE.org MITRE

published 2020-05-06modified 2026-08-11

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Related entries.

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+1043 more

references (7)

External citations — patches, advisories, analysis.

scry

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