Vulnerability · Published Oct 26, 2026 · Assigned by VulnCheck

CVE-2026-116738VMime through 0.9.2 Stack-Based Buffer Overflow via uuencode Decoder

High 8.8

In plain English

A high-severity stack buffer overflow in vmime from kisli. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 54% of all known vulnerabilities).

Severity (CVSS 3.1)8.8High

Exploit odds (30 days)0.7%top 45.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

VMime through 0.9.2 contains an integer underflow in the uuEncoder::decode function that allows remote attackers to trigger a stack-based buffer overflow via crafted uuencoded MIME parts. Attackers can send an email with a uuencoded line whose length character is 'b' but is not a 'begin' line, corrupting stack memory to crash the application or potentially execute code.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	libvmime	no fix listed	DEBIAN-CVE-2026-116738
Debian:13	libvmime	no fix listed	DEBIAN-CVE-2026-116738
Ubuntu:22.04:LTS	libvmime	no fix listed	UBUNTU-CVE-2026-116738
Ubuntu:24.04:LTS	libvmime	no fix listed	UBUNTU-CVE-2026-116738
Ubuntu:26.04:LTS	libvmime	no fix listed	UBUNTU-CVE-2026-116738
Ubuntu:26.10	libvmime	no fix listed	UBUNTU-CVE-2026-116738

Affected products (as reported)

Vendor	Product	Versions
kisli	vmime	0 – through 0.9.2

Weakness: CWE-121 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References

Pull Request #363 issue-tracking, patch
Patch Commit patch
https://github.com/kisli/vmime product
https://github.com/kisli/vmime/blob/v0.9.2/src/vmime/utility/encoder/uuEncoder.cpp#L185-L190 technical-description
https://hackmd.io/@haindpwn/vmime-uuencode-decoder-oob-write third-party-advisory
VulnCheck Advisory: VMime through 0.9.2 Stack-Based Buffer Overflow via uuencode Decoder third-party-advisory