CVE-2026-116739
VMime through 0.9.2 Uninitialized Stack Memory Disclosure via uuencode Decoder
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.
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckFix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| vmime kisli kisli/vmime
github |
≥ 0; ≤ 0.9.2 (affected, custom)
Other versions: unaffected |
CNA: VulnCheck |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 5.3 medium |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N | CNA: VulnCheck |
| 3.1 / 4.3 medium |
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N | CNA: VulnCheck |
Exploit evidence
- https://hackmd.io/@haindpwn/vmime-uuencode-decoder-oob-write
exploit · ADP: CISA-ADP
References
- https://github.com/kisli/vmime/pull/363CNA: VulnCheck · issue-tracking, patch
- https://github.com/kisli/vmime/commit/e85925eddc638939f0eeb7ee55ec047d04a760d8CNA: VulnCheck · patch
- https://github.com/kisli/vmimeCNA: VulnCheck · product
- https://github.com/kisli/vmime/blob/v0.9.2/src/vmime/utility/encoder/uuEncoder.cpp#L311CNA: VulnCheck · technical-description
- https://hackmd.io/@haindpwn/vmime-uuencode-decoder-oob-writeCNA: VulnCheck · third-party-advisory
- https://www.vulncheck.com/advisories/vmime-through-0.9.2-uninitialized-stack-memory-disclosure-via-uuencode-decoderCNA: VulnCheck · third-party-advisory
- https://hackmd.io/@haindpwn/vmime-uuencode-decoder-oob-writeADP: CISA-ADP · exploit
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