Security Resilience

CVE-2023-36355

Memory Safety in Tp-Link Tl-Wr940N Firmware

Public PoCMemory Safety
Published
22 June 2023
Modified
21 November 2024
CVSS Score v3.1 9.9
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.32 98th percentile
Risk Priority 87 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-36355 is a critical-severity Classic Buffer Overflow (CWE-120) vulnerability in Tp-Link Tl-Wr940N Firmware. Its CVSS base score is 9.9 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique NTDS (T1003.003); ranked in the top 2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

TP-Link TL-WR940N V4 contains a buffer overflow vulnerability in the ipStart parameter of the /userRpm/WanDynamicIpV6CfgRpm endpoint, classified under CWE-120. The flaw was disclosed on 2023-06-22 and carries a CVSS 3.1 score of 9.9, reflecting network-accessible, low-complexity attack conditions with low privileges required and impacts to confidentiality, integrity, and availability.

An attacker with limited privileges can submit a crafted GET request to the affected endpoint, triggering the overflow and resulting in a denial of service. The same conditions enable potential further impacts consistent with the CVSS vector, though public descriptions emphasize service disruption on the wireless router.

Public references consist of exploit artifacts published on PacketStorm and detailed write-ups on GitHub that demonstrate the buffer write out-of-bounds condition. The associated EPSS score reached a peak of 0.4295 with a current value of 0.3434, indicating a material rise in exploitation interest after disclosure.

EU & UK References

Vulnerability Data

TP-Link TL-WR940N V4 was discovered to contain a buffer overflow via the ipStart parameter at /userRpm/WanDynamicIpV6CfgRpm. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted GET request.

CWE(s)
CWE-120

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003.003 NTDS Credential Access
Adversaries may attempt to access or create a copy of the Active Directory domain database in order to steal credential information, as well as obtain other information about domain members such as devices, users, and access rights.
attack.mitre.org →
T1003.004 LSA Secrets Credential Access
Adversaries with SYSTEM access to a host may attempt to access Local Security Authority (LSA) secrets, which can contain a variety of different credential materials, such as credentials for service accounts.
attack.mitre.org →
T1003.006 DCSync Credential Access
Adversaries may attempt to access credentials and other sensitive information by abusing a Windows Domain Controller's application programming interface (API)(Citation: Microsoft DRSR Dec 2017) (Citation: Microsoft GetNCCChanges) (Citati…
attack.mitre.org →
T1003.008 /etc/passwd and /etc/shadow Credential Access
Adversaries may attempt to dump the contents of <code>/etc/passwd</code> and <code>/etc/shadow</code> to enable offline password cracking.
attack.mitre.org →
T1010 Application Window Discovery Discovery
Adversaries may attempt to get a listing of open application windows.
attack.mitre.org →
T1012 Query Registry Discovery
Adversaries may interact with the Windows Registry to gather information about the system, configuration, and installed software.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-54887Same product: Tp-Link Tl-Wr940N
CVE-2025-6151Same product: Tp-Link Tl-Wr940N
CVE-2023-36359Same product: Tp-Link Tl-Wr940N
CVE-2023-36358Same product: Tp-Link Tl-Wr940N
CVE-2023-36354Same product: Tp-Link Tl-Wr940N
CVE-2026-11410Same product: Tp-Link Tl-Wr940N
CVE-2026-11409Same product: Tp-Link Tl-Wr940N
CVE-2024-25139Same vendor: Tp-Link
CVE-2025-25900Same vendor: Tp-Link
CVE-2024-48714Same vendor: Tp-Link

Affected Assets

tp-link
tl-wr940n firmware
all versions

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V5.2.1

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.

SC-27 Platform-independent Applications
addresses: CWE-120

Platform-independent managed code eliminates the need for unchecked native buffer copies that are the root cause of classic buffer overflows.

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.

ID.RA-01 partial match
blocks

Vulnerability identification processes such as code review or scanning detect classic buffer overflows before exploitation.

PR.PS-02 partial match
blocks

Routine patching replaces vulnerable code containing unchecked buffer copies with corrected versions.

PR.PS-06 partial match
blocks

Secure development practices directly enforce bounds checking and input validation that prevent classic buffer overflows.

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.

A.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
removes

References