CVE-2026-7839

criticalpriority · track · 0OT risk · elevatedEPSS 0.007 · 51 %ileDEEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.66% (51st) EPSS
CVSS 9.1 · critical
Is it mine?
4 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

UltraVNC repeater through 1.8.2.2 initializes the HTTP administration server with a hardcoded default password. In repeater/webgui/settings.c:197, when settings2.txt is absent on first run the repeater writes the literal string "adminadmi2" as the admin password via strcpy_s(saved_password, 64, "adminadmi2"). The HTTP Basic-auth handler wi_decode_auth() checks this password without rate-limiting or lockout. Any remote attacker who can reach the repeater HTTP port (default TCP 80) can authenticate as administrator using the well-known default credential on a fresh or unmodified installation, gaining full control of the repeater configuration including allow/deny rules and session visibility.

01

cvss

Technical severity, 0–10. One row per scoring source.

9.1
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.3–9.1

v3.19.1criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Nsecondary · ENISA EU
v3.19.1criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Nsecondaryexploitability 3.9 · impact 5.2
v3.18.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-798US
04

affected products (4)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-2162UltraVNC: Mehrere SchwachstellenDeutsch2026-06-30csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in UltraVNC ausnutzen, um beliebigen Programmcode auszuführen, vertrauliche Informationen offenzulegen, Daten zu manipulieren, und einen Denial of Service zu verursachen.

06

also known as (3)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdcert_bundnvdNVDCVE.orgMITRE
published 2026-07-01modified 2026-10-25
08

references (9)

External citations — patches, advisories, analysis.

scry

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