Vulnerability · Published Oct 26, 2026 · Assigned by VulnCheck
CVE-2026-116739VMime through 0.9.2 Uninitialized Stack Memory Disclosure via uuencode Decoder
Medium 4.3
In plain English
A medium-severity security flaw in vmime from kisli. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 17% of all known vulnerabilities).
Severity (CVSS 3.1)4.3Medium
Exploit odds (30 days)0.3%top 83.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
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. 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | libvmime | no fix listed | DEBIAN-CVE-2026-116739 |
| Debian:13 | libvmime | no fix listed | DEBIAN-CVE-2026-116739 |
| Ubuntu:22.04:LTS | libvmime | no fix listed | UBUNTU-CVE-2026-116739 |
| Ubuntu:24.04:LTS | libvmime | no fix listed | UBUNTU-CVE-2026-116739 |
| Ubuntu:26.04:LTS | libvmime | no fix listed | UBUNTU-CVE-2026-116739 |
| Ubuntu:26.10 | libvmime | no fix listed | UBUNTU-CVE-2026-116739 |
Affected products (as reported)
Weakness: CWE-908 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
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#L311 technical-description
- https://hackmd.io/@haindpwn/vmime-uuencode-decoder-oob-write third-party-advisory
- VulnCheck Advisory: VMime through 0.9.2 Uninitialized Stack Memory Disclosure via uuencode Decoder third-party-advisory