CVE-2026-77708: Stack Overflow (CVSS 5.9)

Description

A pre-authentication stack-based buffer overflow vulnerability has been identified in the SonicOS TACACS+ authentication client, which in specific conditions could potentially enable a remote unauthenticated attacker to cause an application level denial of service.

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CVSS v3.1 Score

5.9

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0066

Probability of exploitation

0.52%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-121 CWE-121

References

Other References

https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2026-0014

Frequently Asked Questions

What is CVE-2026-77708? +

A pre-authentication stack-based buffer overflow vulnerability has been identified in the SonicOS TACACS+ authentication client, which in specific conditions could potentially enable a remote unauthenticated attacker to cause an application level denial of service. It has a CVSS v3.1 base score of 5.9 (MEDIUM).

How severe is CVE-2026-77708? +

CVE-2026-77708 has a CVSS v3.1 score of 5.9 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0066, placing it in the 1th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-77708? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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