Cyber Resilience

CVE-2022-20700

Memory Safety in Cisco Rv340 Firmware ≤ 1.0.03.24

CISA KEVActive ExploitationEUVD ExploitedMemory Safety
Published
10 February 2022
Modified
28 October 2025
KEV Added
03 March 2022
Patch / advisory
CVSS Score v3.1 10.0
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.057 92th percentile
Risk Priority 100 floored blend · peak EPSS

Summary

CVE-2022-20700 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 Exploitation for Privilege Escalation (T1068); ranked in the top 8% 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 affect Cisco Small Business RV160, RV260, RV340, and RV345 Series Routers and are tracked under CVE-2022-20700. The issues include stack-based buffer overflows and out-of-bounds writes that can be triggered over the network, leading to outcomes such as arbitrary code execution, privilege escalation, command execution, authentication bypass, execution of unsigned software, and denial of service. The vulnerabilities carry a maximum CVSS score of 10.0.

An unauthenticated remote attacker can exploit the flaws by sending specially crafted network requests to affected devices, achieving any of the impacts listed above without requiring user interaction or prior credentials.

The Cisco Security Advisory recommends applying the vendor-supplied firmware updates for each affected router model and following the configuration hardening steps outlined in the advisory. The entry also appears in the CISA Known Exploited Vulnerabilities catalog, confirming observed in-the-wild exploitation.

EPSS scores for this CVE rose from a low baseline to a peak of 0.3221, indicating that exploitation interest increased after public disclosure and that the issue merits renewed attention.

EU & UK References

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

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2022-20705Same product: Cisco Rv160
CVE-2022-20701Same product: Cisco Rv340both on KEV
CVE-2022-20703Same product: Cisco Rv160both on KEV
CVE-2022-20707Same product: Cisco Rv340
CVE-2022-20699Same product: Cisco Rv340both on KEV
CVE-2022-20708Same product: Cisco Rv340both on KEV
CVE-2023-20109Same vendor: Ciscoboth on KEV
CVE-2020-3118Same vendor: Ciscoboth on KEV
CVE-2025-20352Same vendor: Ciscoboth on KEV
CVE-2018-0171Same vendor: Ciscoboth on KEV

Affected Assets

cisco
rv340 firmware
≤ 1.0.03.24
cisco
rv340w firmware
≤ 1.0.03.24
cisco
rv345 firmware
≤ 1.0.03.24
cisco
rv345p firmware
≤ 1.0.03.24
cisco
rv160 firmware
≤ 1.0.01.05
cisco
rv160w firmware
≤ 1.0.01.05
cisco
rv260 firmware
≤ 1.0.01.05
cisco
rv260p firmware
≤ 1.0.01.05
cisco
rv260w firmware
≤ 1.0.01.05

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 2 hardening rules · 2 OS baselines
Validate
Prove the fix (OWASP ASVS)

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.

addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

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.

PR.PS-06 mostly match
prevents

Secure-development practices directly prevent introduction of stack buffer overflows.

ID.RA-01 partial match
prevents

Vulnerability scanning can discover stack buffer overflows but does not prevent their introduction.

PR.PS-02 partial match
prevents

Patching eliminates known instances of the weakness after discovery.

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.

finds

Security testing (fuzzing, static analysis) detects stack overflows before release.

prevents

Secure SDLC mandates buffer-safety practices that directly prevent stack overflows.

prevents

Application security requirements can specify buffer-size and input-validation rules.

prevents

Secure architecture principles include memory-safety and least-privilege stack usage.

prevents

Secure coding standards explicitly forbid unsafe buffer handling that causes CWE-121.

prevents

Change management can enforce review gates that catch unsafe memory operations before deployment.

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` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248594 OL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution. prevents CWE-121
Oracle Linux 9 (1 rule)
  • V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-121

References