CVE-2026-116739 kisli CVE debrief

Who should care

Defenders responsible for VMime installations should assess exposure and prioritize patching to prevent potential information disclosure. This includes operators, platform administrators, vulnerability management teams, and security teams who need to verify and patch affected systems. The vulnerability can lead to potential information disclosure via uninitialized stack memory, and defenders should review and update affected systems and software to prevent

Why it matters

Defenders should prioritize verifying and patching VMime installations to prevent potential information disclosure via uninitialized stack memory.

• Potential information disclosure via uninitialized stack memory
• Need to verify and patch VMime installations
• Potential for attackers to exploit vulnerability

Technical summary

VMime through 0.9.2 contains an information disclosure vulnerability in the uuEncoder::decode function that writes uninitialized stack memory into decoded output for over-long lines. This can be exploited by sending a crafted uuencode or x-uuencode MIME part with a large line length byte to leak up to 15 bytes of stack contents per line in decoded attachments. The vulnerability affects VMime installations and can be mitigated by verifying and patching affected systems. Defenders should prioritize verifying and patching VMime installations to prevent potential information disclosure.

Defensive priority

Defenders should prioritize verifying and patching VMime installations to prevent potential information disclosure.

Recommended defensive actions

• Verify and patch VMime installations to prevent potential information disclosure
• Review and update affected systems and software
• Monitor for potential exploitation attempts
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record and source item provide details on the vulnerability in VMime through 0.9.2, including the affected versions and a description of the issue. The vulnerability is caused by the uuEncoder::decode function writing uninitialized stack memory into decoded output for over-long lines. Attackers can send a crafted uuencode or x-uuencode MIME part with a large line length byte to leak up to 15 bytes of stack contents per line in decoded attachments. Defenders should verify and patch VMime installations to prevent potential The

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.