High 7.5Published Oct 20, 2025

CVE-2025-11678Stack-based Buffer Overflow in libwebsockets DNS response parsing

Updated under an hour ago (Oct 28, 2026, 1:40 AM ET)

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It affects warmcat libwebsocket. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for warmcat libwebsocket

Exploited in the last 30 days

Stack-based Buffer Overflow in lws_adns_parse_label in warmcat libwebsockets allows, when the LWS_WITH_SYS_ASYNC_DNS flag is enabled during compilation, to overflow the label_stack, when the attacker is able to sniff a DNS request in order to craft a response with a matching id containing a label longer than the maximum.

CVSS: 7.5 HIGH (v4.0, CNA)CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weakness (CWE): CWE-121
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Nozomi
NVD analysis: Deferred
Record last updated: Oct 20, 2025
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

warmcat libwebsocket warmcat:libwebsocket (from the name)	from 4.0 through 4.4.2; from 4.0 through 4.3.6	CNA record

References

References

https://libwebsockets.org/git/libwebsockets/commit?id=2bb9598562b37c942ba5b04bcde3f7fdf66a9d3a	patch, vendor-advisory
https://www.nozominetworks.com/labs/vulnerability-advisories-cve-2025-11678	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.