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TI-2026-70070 Aliases CVE-2026-15340

Buffer overflow in Savannah lwIP SMTP client

Priority MEDIUM 48CWE-120Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-120 and the CVSS impact.

Summary

The lwIP SMTP client from Savannah, from version 2.2.1, does not check the size of inputs before copying them into a buffer (CWE-120). A network attacker needs no privileges or user interaction to overflow the buffer, with high impact on confidentiality, integrity and availability.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

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

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00367 30th percentileScored 2026-11-07
Fix Fixed lwIP SMTP client (Savannah): patch_125_smtp_txbuf.diff, git commit (614420f82c8729d070e01464c0dddb3c9525c772)

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
SavannahlwIP SMTP client2.2.1patch_125_smtp_txbuf.diff, git commit (614420f82c8729d070e01464c0dddb3c9525c772)Patch availableCNA
  • lwIP SMTP client VendorSavannah Affected 2.2.1 Fixed in patch_125_smtp_txbuf.diff, git commit (614420f82c8729d070e01464c0dddb3c9525c772) Patch available CNA

Remediation

Apply the fix in patch_125_smtp_txbuf.diff or git commit 614420f82c8729d070e01464c0dddb3c9525c772 to the lwIP SMTP client.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA lwIP SMTP client (Savannah) Fixed in patch_125_smtp_txbuf.diff, git commit (614420f82c8729d070e01464c0dddb3c9525c772)

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-09 Threatist record created from CVE-2026-15340
  2. 2026-10-11 CISA SSVC decision points changed
  3. 2026-10-13 Affected versions changed · Red Hat
  4. 2026-10-13 CVSS score added · Red Hat

References

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences