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Vulnerability record · CVE-2026-38821 · published 28 August 2026

CVE-2026-38821: Heap-based buffer overflow vulnerability

A heap-based buffer overflow vulnerability exists in openNDS before 11.0.0 that allows an unauthenticated attacker on the captive portal network to crash the openNDS daemon (denial of service) and potentially achieve remote code execution. This is in http_microhttpd.c.

7.1 CVSS 3.1 High EPSS 0.31% · top 79.0% CWE-122 · Heap-based buffer overflow Deferred
7.1CVSS 3.1 base score
0.31%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
1References
9 Sep 2026Last modified by NVD

Description

A heap-based buffer overflow vulnerability exists in openNDS before 11.0.0 that allows an unauthenticated attacker on the captive portal network to crash the openNDS daemon (denial of service) and potentially achieve remote code execution. This is in http_microhttpd.c.

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

References

LinkTags
https://github.com/openNDS/openNDS/commit/3b5f7ef40cd048826d3c4a16f61a73a1768fd5a9

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Source: NIST National Vulnerability Database (record CVE-2026-38821), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.