CVE-2026-15340

Savannah lwIP SMTP client Classic Buffer Overflow

Savannah lwIP SMTP client

CVSS

9.8Critical

ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV

Exploit odds (EPSS)0.60%Chance of exploitation activity in the next 30 days, higher than 47% of CVEs. Scored 23 Oct 2026FIRST EPSS

Fixed inNone listedNo source names a fixed version. Check the vendor advisory below

Published9 Oct 2026Updated 11 Oct 2026CVE List

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

lwIP SMTP client does not check the size of inputs, potentially allowing a buffer overflow.

Text from CVE List

lwIP SMTP clientaffected: 2.2.1CVE List
lwIP SMTP clientunaffected: patch_125_smtp_txbuf.diffCVE List
lwIP SMTP clientunaffected: git commit (614420f82c8729d070e01464c0dddb3c9525c772)CVE List