CVE-2022-20703
Memory Safety in Cisco Rv340 Firmware ≤ 1.0.03.24
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2022-20703 is a critical-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Cisco Rv340 Firmware. Its CVSS base score is 10.0 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Security Account Manager (T1003.002); ranked in the top 5% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
Multiple vulnerabilities tracked under CVE-2022-20703 affect Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers. The issues, assigned a CVSS score of 10.0, stem from flaws including stack-based buffer overflows (CWE-121) and improper certificate validation (CWE-295) that collectively enable arbitrary code execution, privilege escalation, command execution, authentication bypass, execution of unsigned software, and denial of service.
Remote attackers can exploit the flaws over the network without authentication or user interaction, leveraging the routers' exposed management interfaces to achieve any of the listed impacts and fully compromise affected devices.
The Cisco Security Advisory at tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-smb-mult-vuln-KA9PK6D and related Zero Day Initiative reports provide mitigation guidance and patch information for the affected router firmware. The associated EPSS score has remained flat at 0.02 with no material increase since disclosure.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2022-25953
Vulnerability Data
Multiple vulnerabilities in Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers could allow an attacker to do any of the following: Execute arbitrary code Elevate privileges Execute arbitrary commands Bypass authentication and authorization protections Fetch and run unsigned…
more
software Cause denial of service (DoS) For more information about these vulnerabilities, see the Details section of this advisory.
- CWE(s)
- KEV Date Added
- 03 March 2022
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 14 hardening rules · 4 OS baselines
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Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
When certificates are used to establish component provenance, the control requires correct certificate validation procedures.
Mandates approved trust anchors and issuance policies, directly preventing acceptance of unvalidated or untrusted certificates.
Correct system time is required for proper enforcement of certificate notBefore/notAfter dates and time-based revocation checks.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Vulnerability scanning can discover stack buffer overflows but does not prevent their introduction.
Assessing authenticity/integrity of acquired software often relies on code-signing certificate validation.
Certificate-based authentication of users/services/hardware directly depends on correct validation.
Identity assertions conveyed via certificates require validation to be verified.
Proper certificate validation is a core mechanism for protecting data-in-transit confidentiality and integrity.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).
Oracle Linux 8 (4 rules)
- V-248574 YUM must be configured to prevent the installation of patches, service packs, device drivers, or OL 8 system components that have not been digitally signed using a certificate that is recognized and approved by the organization. blocks CWE-295
- V-248531 OL 8, for PKI-based authentication, must validate certificates by constructing a certification path (which includes status information) to an accepted trust anchor. blocks CWE-295
- V-248575 OL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295
Oracle Linux 9 (1 rule)
- V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. blocks CWE-121
RHEL 7 (2 rules)
- V-204447 The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295
- V-204448 The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295
RHEL 8 (2 rules)
- V-230264 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295
- V-230265 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. blocks CWE-295