DEBIAN-CVE-2026-42859
Neat VNC is a VNC server library. Prior to 0.9.6, a pre-authentication stack buffer overflow exists in neatvnc in the RSA-AES security type handler. An unauthenticated remote attacker who can reach the VNC listening socket can send a crafted security type 5 (RSA-AES) or security type 129 (RSA-AES-256) handshake with an oversized client RSA public key, causing rsa_aes_send_challenge in src/auth/rsa-aes.c to overflow a 1024-byte on-stack buffer when encrypting the server challenge. This results in at least a denial of service via server crash. This vulnerability is fixed in 0.9.6.
DEBIAN-CVE-2026-42859
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-42859
neatvnc
Source reference: /affected/0/package/name
- Affected versions
- 0.5.4+dfsg-1
Source reference:
/affected/0/versions0.5.4+dfsg-2~exp1Source reference:
/affected/0/versions0.6.0+dfsg-1Source reference:
/affected/0/versions0.6.0+dfsg-2Source reference:
/affected/0/versions0.6.0+dfsg-3Source reference:
/affected/0/versions0.6.0+dfsg-4Source reference:
/affected/0/versions0.7.0+dfsg-1Source reference:
/affected/0/versions0.7.0+dfsg-1~exp1Source reference:
/affected/0/versions0.7.1+dfsg-1Source reference:
/affected/0/versions0.7.1+dfsg-2Source reference:
/affected/0/versions0.8.0+dfsg-1Source reference:
/affected/0/versions0.8.0+dfsg-2Source reference:
/affected/0/versions0.8.0+dfsg-3Source reference:
/affected/0/versions0.9.1+dfsg-1Source reference:
/affected/0/versions0.9.1+dfsg-1.1Source reference:
/affected/0/versions1.0.0+dfsg-1~exp1Source reference:
/affected/0/versions1.0.1+dfsg-1Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
neatvnc
Source reference: /affected/1/package/name
- Affected versions
- 0.9.1+dfsg-1
Source reference:
/affected/1/versions0.9.1+dfsg-1.1Source reference:
/affected/1/versions1.0.0+dfsg-1~exp1Source reference:
/affected/1/versions1.0.1+dfsg-1Source reference:
/affected/1/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
neatvnc
Source reference: /affected/2/package/name
- Affected versions
- 0.9.1+dfsg-1
Source reference:
/affected/2/versions - Fixed versions
- 0.9.1+dfsg-1.1
Source reference:
/affected/2/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "neatvnc",
"purl": "pkg:deb/debian/neatvnc?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"0.5.4+dfsg-1",
"0.5.4+dfsg-2~exp1",
"0.6.0+dfsg-1",
"0.6.0+dfsg-2",
"0.6.0+dfsg-3",
"0.6.0+dfsg-4",
"0.7.0+dfsg-1",
"0.7.0+dfsg-1~exp1",
"0.7.1+dfsg-1",
"0.7.1+dfsg-2",
"0.8.0+dfsg-1",
"0.8.0+dfsg-2",
"0.8.0+dfsg-3",
"0.9.1+dfsg-1",
"0.9.1+dfsg-1.1",
"1.0.0+dfsg-1~exp1",
"1.0.1+dfsg-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42859.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "neatvnc",
"purl": "pkg:deb/debian/neatvnc?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"0.9.1+dfsg-1",
"0.9.1+dfsg-1.1",
"1.0.0+dfsg-1~exp1",
"1.0.1+dfsg-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42859.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.9.1+dfsg-1.1"
}
]
}
],
"package": {
"name": "neatvnc",
"purl": "pkg:deb/debian/neatvnc?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"0.9.1+dfsg-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42859.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #57676 · Revision 1
- Added to Heist Feed
- Publisher date