CVE-2026-44041

mediumpriority · track · 26EPSS 0.004 · 35 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.41% (35th) EPSS

CVSS 6.5 · medium

Is it mine?

4 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-28

UltraVNC through 1.8.2.2 contains an out-of-bounds read in the wide-string to multibyte conversion helper. In rfb/dh.cpp:204, the vncWc2Mb() function passes a caller-supplied WCHAR pointer to wcslen() before any bounds check. If the caller provides a wide-character buffer that is not properly NUL-terminated, wcslen() reads past the end of the buffer until it encounters a NUL wchar, resulting in an out-of-bounds read. Under typical Win32 API usage this requires an abnormal caller contract. Impact is limited to a potential information disclosure from adjacent memory regions or a process crash (denial of service) if the over-read crosses a page boundary.

cvss

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

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Lprimary · NVD / NIST USexploitability 3.9 · impact 2.5

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · ENISA EU

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondaryexploitability 2.8 · impact 1.4

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)

ssvc

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

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-125US

affected products (4)

Products and version ranges known to be affected.

UltraVNC UltraVNC <1.8.2.4all versionscert_bundDE
UltraVNC UltraVNC< 1.8.2.4cert_bundDE
Uvnc UltraVNC≤ 0 ≤1.8.2.2enisa_euvdEU
uvnc ultravnc≤ 1.8.2.2nvdUScpe:2.3:a:uvnc:ultravnc:*:*:*:*:*:*:*:*

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.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2026-07-01modified 2026-10-25

references (9)

External citations — patches, advisories, analysis.

scry

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