Security Resilience

CVE-2023-27332

Memory Safety in Tp-Link Archer Ax21 Firmware 1.1.3

Memory Safety
Published
03 May 2024
Modified
06 August 2025
CVSS Score v3 8.8
Click a component to see what it means
Raw vectorCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0072 53th percentile
Risk Priority 66 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-2023-27332 is a high-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Tp-Link Archer Ax21 Firmware. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique /etc/passwd and /etc/shadow (T1003.008); ranked in the top 47% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

TP-Link Archer AX21 tdpServer Logging Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of TP-Link Archer AX21 routers. Authentication is not required to exploit this vulnerability. The specific flaw…

more

exists within the logging functionality of the tdpServer program, which listens on UDP port 20002. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. . Was ZDI-CAN-19898.

CWE(s)
CWE-121

Related Threats

MITRE ATT&CK Enterprise Techniques

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 →
T1007 System Service Discovery Discovery
Adversaries may try to gather information about registered local system services.
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 →
T1016.002 Wi-Fi Discovery Discovery
Adversaries may search for information about Wi-Fi networks, such as network names and passwords, on compromised systems.
attack.mitre.org →
T1020 Automated Exfiltration Exfiltration
Adversaries may exfiltrate data, such as sensitive documents, through the use of automated processing after being gathered during Collection.
attack.mitre.org →
T1020.001 Traffic Duplication Exfiltration
Adversaries may leverage traffic mirroring in order to automate data exfiltration over compromised infrastructure.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-27333Same product: Tp-Link Archer Ax21
CVE-2023-27346Same product: Tp-Link Archer Ax21
CVE-2023-31710Same product: Tp-Link Archer Ax21
CVE-2024-9284Same vendor: Tp-Link
CVE-2023-1389Same product: Tp-Link Archer Ax21
CVE-2026-1457Same vendor: Tp-Link
CVE-2023-44448Same vendor: Tp-Link
CVE-2026-1871Same vendor: Tp-Link
CVE-2023-27359Same product: Tp-Link Archer Ax21
CVE-2025-15608Same vendor: Tp-Link

Affected Assets

tp-link
archer ax21 firmware
1.1.3

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)

—

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and analysis can discover stack-buffer overflows before deployment.

SI-10 Information Input Validation good match

Input validation directly stops untrusted data from exceeding stack buffer bounds.

SI-16 Memory Protection good match

Memory-protection mechanisms limit the ability to execute injected code after a stack overflow.

SA-8 Security and Privacy Engineering Principles partial match

Secure-engineering principles include bounds-checked coding and safe buffer handling that avoid introducing the flaw.

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

PR.PS-02 partial match
blocks

Patching eliminates known instances of the weakness after discovery.

PR.PS-06 partial match
blocks

Secure-development practices directly prevent introduction of stack 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

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 (1 rule)
  • V-248594 OL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution. blocks CWE-121
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

References