CVE-2023-6906 | Totolink A7100RU HTTP POST Request main buffer overflow

Exp

A vulnerability, which was classified as critical, was found in Totolink A7100RU 7.4cu.2313_B20191024. Affected is the function main of the file /cgi-bin/cstecgi.cgi?action=login of the component HTTP POST Request Handler. The manipulation of the argument flag with the input ie8 leads to buffer overflow. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-248268. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.

Published: 2023-12-17 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-6906 is rated High Exploit Risk (82.6/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.85%). 1 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +1.66% over the last day, indicating growing attacker interest. Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2023-6906

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-6906

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.19% 1.85% +1.66%
2 2025-11-21 0.31% 0.19% -0.11%
3 2025-11-18 — 0.31% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-6906

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
10.0 2.0 HIGH
AV:N/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 10.0 10.0 [email protected]

Weakness enumeration for CVE-2023-6906

Affected software / configurations for CVE-2023-6906

Vendor Product Version Raw CPE
totolink a7100ru_firmware 7.4cu.2313_b20191024 cpe:2.3:o:totolink:a7100ru_firmware:7.4cu.2313_b20191024:*:*:*:*:*:*:*

References for CVE-2023-6906

URL Tags
https://github.com/unpWn4bL3/iot-security/blob/main/1.md Exploit Third Party Advisory
https://vuldb.com/?ctiid.248268 Permissions Required Third Party Advisory
https://vuldb.com/?id.248268 Third Party Advisory
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