Vulnerability in Cisco Firepower Threat Defense (FTD) Software (CVE-2021-34761)
Summary
Vulnerability in Cisco Firepower Threat Defense (FTD) Software (CVE-2021-34761). Data can be tampered with by attackers.
Original description
The description as published by the source.
A vulnerability in Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, local attacker to overwrite or append arbitrary data to system files using root-level privileges. The attacker must have administrative credentials on the device. This vulnerability is due to incomplete validation of user input for a specific CLI command. An attacker could exploit this vulnerability by authenticating to the device with administrative privileges and issuing a CLI command with crafted user parameters. A successful exploit could allow the attacker to overwrite or append arbitrary data to system files using root-level privileges.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2021-34761 has been found in Cisco Firepower Threat Defense (FTD) Software.
Data can be tampered with by attackers. CVSS score: 4.4/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Cisco Firepower Threat Defense (FTD) Software CVE-2021-34761" on the vendor's site.
CVE-2021-34761 (Cisco Firepower Threat Defense (FTD) Software) — CWE-20 / CVSS v3 4.4
Attack vector: local / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-20) exists in Cisco Firepower Threat Defense (FTD) Software.
Check the vendor advisory for the affected versions of Cisco Firepower Threat Defense (FTD) Software.
Severity: Medium (CVSS 4.4/10). Data can be tampered with by attackers.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Cisco Firepower Threat Defense (FTD) Software を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- web tools.cisco.com
- web nvd.nist.gov
- web github.com