Cyber Resilience

CVE-2023-31475

CriticalPublic PoC

Published: 11 May 2023

Published
11 May 2023
Modified
27 January 2025
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.2211 95.9th percentile
Risk Priority 33 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-31475 is a critical-severity Classic Buffer Overflow (CWE-120) vulnerability in Gl-Inet Gl-S20 Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 4.1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis

CVE-2023-31475 is a buffer overflow vulnerability in the guci2_get() function within libglutil.so on GL.iNet devices running firmware versions prior to 3.216. The flaw occurs when an item is retrieved from a UCI context and its value is copied into a fixed-size character buffer without performing a bounds check.

The vulnerability can be exploited remotely by unauthenticated attackers over the network. Successful exploitation grants full control over confidentiality, integrity, and availability, enabling outcomes such as arbitrary code execution or device takeover, consistent with the CVSS 9.8 rating.

Vendor references direct users to firmware 3.216 and later releases that address the issue. The associated EPSS score rose from lower values to a peak of 0.2581 before receding to the current 0.2211, indicating measurable post-disclosure exploitation interest.

EU & UK References

Vulnerability details

An issue was discovered on GL.iNet devices before 3.216. The function guci2_get() found in libglutil.so has a buffer overflow when an item is requested from a UCI context, and the value is pasted into a char pointer to a buffer…

more

without checking the size of the buffer.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

gl-inet
gl-s20 firmware
≤ 3.216
gl-inet
gl-x3000 firmware
≤ 3.216
gl-inet
gl-mt3000 firmware
≤ 3.216
gl-inet
gl-mt2500 firmware
≤ 3.216
gl-inet
gl-mt2500a firmware
≤ 3.216
gl-inet
gl-axt1800 firmware
≤ 3.216
gl-inet
gl-a1300 firmware
≤ 3.216
gl-inet
gl-ax1800 firmware
≤ 3.216
gl-inet
gl-sft1200 firmware
≤ 3.216
gl-inet
gl-mt1300 firmware
≤ 3.216
+22 more product configuration(s) — see NVD for full list

Mitigating Controls

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-120

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

References