cve.bz

CVE-2026-123959 totolink ca300-poe: Classic Buffer Overflow

8.5 highEPSS 0.8%

High (8.5) in totolink ca300-poe. EPSS 0.8% estimated probability of exploitation activity in the next 30 days.

On this page
A security flaw has been discovered in TOTOLINK CA300-PoE 6.2c.884. The impacted element is the function setLanguageCfg of the file /cgi-bin/cstecgi.cgi. Performing a manipulation of the argument langType results in buffer overflow. The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks.

Severity

CVSS 4.0

8.5 high
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P

CVSS 3.1

9.1 critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
EPSS
0.8% estimated probability of exploitation activity in the next 30 days; 58th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: PoC · Automatable: no · Technical impact: total, assessed 2026-11-10. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
CWEs
CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer
CWE-120 Buffer Copy without Checking Size of Input (Classic Buffer Overflow)
Published
Modified
Assigned by
VulDB (CNA)
NVD analysis
Deferred: the NVD does not plan to analyze it
Record from
the NVD, synced

Ask an AI about this CVE

Show the promptExplain CVE-2026-123959 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-123959?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-123959?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-123959 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.

Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.

Badge for a README or a site

CVE-2026-123959

An image that stays current: it is drawn from the data each time it is fetched (a host that proxies images, as GitHub does, may show its copy for a while). Markdown:

[![CVE-2026-123959](https://cve.bz/cve/badge/CVE-2026-123959.svg)](https://cve.bz/cve/CVE-2026-123959)

HTML:

<a href="https://cve.bz/cve/CVE-2026-123959"><img src="https://cve.bz/cve/badge/CVE-2026-123959.svg" alt="CVE-2026-123959"></a>

Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
TOTOLINK CA300-PoE6.2c.884

Attack patterns (CAPEC)

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-119 (12), CWE-120 (13).

References

Check your stackJSON