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.
CVE-2026-44041
Score 4.3 from GitHub Security Advisory published 2026-07-01. NVD baseline CVSS 6.5; sources differ by 2.2.
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.5
- EG Score
- 4.3(medium)
- EPSS
- 16.8%
- KEV
- Not listed
Published
July 1, 2026
Last Modified
July 2, 2026
Advisory Details (2)
Auto-updated Jul 1, 2026GitHub - ultravnc/UltraVNC: 👁️ UltraVNC Server, UltraVNC Viewer, UltraVNC Repeater and UltraVNC SC | Official repository: https://github.com/ultravnc/UltraVNC · GitHub
https://github.com/ultravnc/UltraVNCVendor Advisories for CVE-2026-44041(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 20× in last 7d / 20× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-06 20:00 UTCEG score recompute
- 2026-07-06 19:59 UTCGHSA enrichment
- 2026-07-06 16:27 UTCEPSS rescore
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-05 21:33 UTCEG score recompute
- 2026-07-05 21:33 UTCGHSA enrichment
- 2026-07-05 02:30 UTCEPSS rescore
- 2026-07-04 23:06 UTCEG score recompute
- 2026-07-04 23:06 UTCGHSA enrichment
- 2026-07-04 06:31 UTCEPSS rescore
- 2026-07-04 00:40 UTCEG score recompute
- 2026-07-04 00:40 UTCGHSA enrichment
- 2026-07-03 02:13 UTCEG score recompute
- 2026-07-03 02:13 UTCGHSA enrichment
- 2026-07-02 16:58 UTCNVD updateCVSS v3 → 6.5
- 2026-07-02 03:47 UTCEG score recompute
- 2026-07-02 03:47 UTCGHSA enrichment
- 2026-07-01 15:07 UTCEPSS rescore
- 2026-07-01 05:22 UTCEG score recompute
- 2026-07-01 05:20 UTCNVD updatefirst tracked
Frequently asked(5)
What is CVE-2026-44041?
When was CVE-2026-44041 disclosed?
Is CVE-2026-44041 actively exploited?
What is the CVSS score of CVE-2026-44041?
How do I remediate CVE-2026-44041?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-44041
Is Your Infrastructure Affected by CVE-2026-44041?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.