How severe is CVE-2023-6906?

CVE-2023-6906 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-6906 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-6906?

CVE-2023-6906 affects Totolink A7100ru Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-6906?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2023-6906 published?

CVE-2023-6906 was published on 2023-12-18 and last updated on 2026-06-17.

CVE-2023-6906

CVE-2023-6906 is a critical-severity vulnerability in Totolink A7100ru Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-120.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Totolink A7100ru Firmware
Published: 2023-12-18
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2023-6906?: 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.
How severe is CVE-2023-6906?: CVE-2023-6906 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-6906 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-6906?: CVE-2023-6906 affects Totolink A7100ru Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-6906?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-6906 published?: CVE-2023-6906 was published on 2023-12-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:totolink:a7100ru_firmware:7.4cu.2313_b20191024:*:*:*:*:*:*:*

More vulnerabilities in Totolink A7100ru Firmware

CVE-2025-44655 — Critical (CVSS 9.8): In TOTOLink A7100RU V7.4, A950RG V5.9, and T10 V5.9, the chroot_local_user option is enabled in the vsftpd.conf. This…
CVE-2023-7095 — Critical (CVSS 9.8): A vulnerability, which was classified as critical, has been found in Totolink A7100RU 7.4cu.2313_B20191024. Affected by…
CVE-2023-33556 — Critical (CVSS 9.8): TOTOLink A7100RU V7.4cu.2313_B20191024 was discovered to contain a command injection vulnerability via the staticGw…
CVE-2023-30054 — Critical (CVSS 9.8): TOTOLINK A7100RU V7.4cu.2313_B20191024 has a Command Injection vulnerability. An attacker can obtain a stable root…
CVE-2023-30053 — Critical (CVSS 9.8): TOTOLINK A7100RU V7.4cu.2313_B20191024 is vulnerable to Command Injection.
CVE-2023-26978 — Critical (CVSS 9.8): TOTOlink A7100RU V7.4cu.2313_B20191024 was discovered to contain a command injection vulnerability via the pppoeAcName…

All CVEs affecting Totolink A7100ru Firmware →

Other CWE-120 (Classic Buffer Overflow) vulnerabilities

CVE-2025-48611 — Critical (CVSS 10.0): In DeviceId of DeviceId.java, there is a possible desync in persistence due to a missing bounds check. This could lead…
CVE-2026-24823 — Critical (CVSS 10.0): Out-of-bounds Write, Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in FASTSHIFT…
CVE-2026-24810 — Critical (CVSS 10.0): Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in rethinkdb (src/cjson modules).…
CVE-2026-24800 — Critical (CVSS 10.0): Out-of-bounds Write, Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in tildearrow…
CVE-2025-9962 — Critical (CVSS 10.0): A buffer overflow vulnerability in Novakon P series allows attackers to gain root permission without prior…
CVE-2010-10016 — Critical (CVSS 10.0): BS.Player version 2.57 (build 1051) contains a vulnerability in its playlist import functionality. When processing .m3u…

Browse all CWE-120 (Classic Buffer Overflow) vulnerabilities →