17
CVEs
2
Critical
6
High
0
KEV
6
PoC
8
Unpatched C/H
0.0%
Patch Rate
0.3%
Avg EPSS
Severity Breakdown
CRITICAL
2
HIGH
6
MEDIUM
8
LOW
1
Monthly CVE Trend
Affected Products (7)
Top Risky CVEs
| CVE | Summary | Severity | CVSS | EPSS | Priority | Signals |
|---|---|---|---|---|---|---|
| CVE-2020-37133 | UltraVNC Launcher 1.2.4.0 contains a denial of service vulnerability in the Repeater Host configuration field that allows attackers to crash the application. Attackers can paste an overly long string of 300 characters into the Repeater Host property to trigger an application crash. [CVSS 7.5 HIGH] | HIGH | 7.5 | 0.0% | 58 |
PoC
No patch
|
| CVE-2019-25600 | UltraVNC Viewer 1.2.2.4 contains a denial of service vulnerability that allows attackers to crash the application by supplying an oversized string to the VNC Server input field. | HIGH | 7.1 | 0.0% | 56 |
PoC
No patch
|
| CVE-2019-25601 | UltraVNC Launcher 1.2.2.4 contains a buffer overflow vulnerability in the Path vncviewer.exe property field that allows local attackers to crash the application by supplying an excessively long. Rated medium severity (CVSS 6.9), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available. | MEDIUM | 6.9 | 0.0% | 55 |
PoC
No patch
|
| CVE-2020-37132 | UltraVNC Launcher 1.2.4.0 contains a denial of service vulnerability in its password configuration properties that allows local attackers to crash the application. [CVSS 6.2 MEDIUM] | MEDIUM | 6.2 | 0.0% | 51 |
PoC
No patch
|
| CVE-2019-25563 | PCHelpWareV2 1.0.0.5 contains a denial of service vulnerability that allows local attackers to crash the application by supplying a malformed image file. Rated medium severity (CVSS 6.2), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available. | MEDIUM | 6.2 | 0.0% | 51 |
PoC
No patch
|
| CVE-2026-7840 | Remote code execution in the UltraVNC repeater (through version 1.8.2.2) allows an unauthenticated attacker who can reach the built-in HTTP administration port (default TCP 80) to overflow a fixed 1000-byte global buffer and corrupt adjacent .bss globals, leading to arbitrary code execution on the host. The flaw lives in wi_senderr() and wi_replyhdr() in repeater/webgui/webutils.c, where the request URI is copied via unchecked sprintf before any authentication check runs. No public exploit identified at time of analysis, but the CVSS 4.0 base score of 9.3 combined with pre-auth network reachability makes this a high-priority issue. | CRITICAL | 9.3 | 1.2% | 48 |
No patch
|
| CVE-2019-25564 | PCHelpWareV2 1.0.0.5 contains a denial of service vulnerability that allows local attackers to crash the application by supplying an excessively long string in the Group field. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available. | MEDIUM | 5.5 | 0.0% | 48 |
PoC
No patch
|
| CVE-2026-7839 | Authentication via hardcoded default credentials in UltraVNC repeater through 1.8.2.2 lets any remote attacker who can reach the HTTP administration port (default TCP 80) log in as administrator. On a fresh or unmodified install where settings2.txt is absent, the repeater writes the literal password 'adminadmi2', and the Basic-auth handler enforces no rate-limiting or lockout, so a single well-known credential yields full control over allow/deny rules and session visibility. Rated CVSS 9.1 (CWE-798); no public exploit identified at time of analysis, though the credential itself is disclosed in the advisory. | CRITICAL | 9.1 | 0.3% | 46 |
No patch
|
| CVE-2026-7838 | Remote code execution in the UltraVNC Viewer (all versions through 1.8.2.2) stems from an integer overflow in the RFB failure-response parser: a malicious or man-in-the-middle VNC server can send a reasonLen of 0xFFFFFFFF that wraps to 0 during buffer sizing, then stream 4 GiB into a 256-byte heap allocation. The flaw is reachable pre-authentication through connection-failure and auth-failure messages, so merely connecting a viewer to an attacker-controlled endpoint can corrupt the heap and potentially execute code as the user running the viewer. No public exploit identified at time of analysis, though the researcher confirmed a reliable heap-buffer-overflow write with AddressSanitizer. | HIGH | 8.7 | 1.2% | 45 |
No patch
|
| CVE-2026-7831 | Denial of service in the UltraVNC viewer (vncviewer) through 1.8.2.2 arises from an off-by-one stack buffer overflow in the RFB ServerInit message handler, where a malicious VNC server advertising a desktop name of exactly 2024 bytes forces ReadString to write a NUL terminator at _dn[2024], one byte past a 2024-byte stack buffer. A rogue or compromised server can crash victims who connect to it (reliable process termination on /GS-hardened builds) and potentially corrupt adjacent stack data on canary-less release builds. No public exploit identified at time of analysis, and the flaw is not listed in CISA KEV; exploitation requires the victim to initiate a connection to the attacker-controlled server. | HIGH | 7.6 | 0.4% | 38 |
No patch
|
| CVE-2026-7830 | Credential disclosure in UltraVNC through 1.8.2.2 lets a passive network observer break the MS-Logon II authentication handshake and recover plaintext usernames and passwords. The rfbUltraVNC_MsLogonIIAuth scheme relies on a Diffie-Hellman exchange whose prime fits in an unsigned 64-bit integer and a private exponent derived from time(NULL)-seeded libc rand(), both of which are trivially solvable, so an attacker who sniffs or man-in-the-middles the exchange derives the shared key in seconds to a minute. There is no public exploit identified at time of analysis and no EPSS/KEV signal supplied; CVSS is 7.4 (AC:H reflecting the need to observe the handshake), and MS-Logon III (X25519 + AES-256-GCM) is not affected. | HIGH | 7.4 | 0.2% | 37 |
No patch
|
| CVE-2026-7829 | Remote code execution in the UltraVNC Repeater (through version 1.8.2.2) allows an authenticated administrator to corrupt stack memory via the web GUI allow/deny rule parser, ultimately achieving code execution on the repeater host. The flaw (CWE-787, out-of-bounds write) is reachable only after admin login, but that barrier is significantly weakened when chained with CVE-2026-7839 (default password), which can hand an attacker the required credentials. There is no public exploit identified at time of analysis and no EPSS/KEV data supplied, so this is currently a credentialed, chainable RCE rather than a confirmed mass-exploited threat. | HIGH | 7.2 | 0.5% | 37 |
No patch
|
| CVE-2026-44041 | Out-of-bounds read in UltraVNC through version 1.8.2.2 allows network-authenticated attackers to potentially crash the VNC server process or leak adjacent memory content via the vncWc2Mb() wide-string conversion helper in rfb/dh.cpp at line 204. The flaw is triggered when wcslen() is called on a caller-supplied WCHAR pointer without a preceding bounds check, enabling memory over-reads if the buffer lacks proper NUL termination. No public exploit code or active exploitation has been identified at time of analysis; the vendor's CVSS 4.3 (Medium) rating reflects the constrained and largely denial-of-service-oriented impact. | MEDIUM | 6.5 | 0.3% | 33 |
No patch
|
| CVE-2026-44040 | UltraVNC through 1.8.2.2 exposes a cryptographically weak VNC authentication challenge generator that an attacker can predict by observing network traffic and enumerating a roughly 31-bit seed space derived from wall-clock time and process ID. Successful seed reconstruction allows the attacker to forge or brute-force valid VNC authentication responses, effectively bypassing the RFB challenge-response mechanism and gaining unauthorized remote desktop access. No public exploit has been identified at time of analysis, and the vulnerability is not currently listed in the CISA KEV catalog; however, the mathematical basis for exploitation is straightforward given the small seed space. | MEDIUM | 6.5 | 0.2% | 33 |
No patch
|
| CVE-2026-3787 | UltraVNC 1.6.4.0 on Windows contains an uncontrolled search path vulnerability in cryptbase.dll that allows local authenticated attackers with low privileges to achieve arbitrary code execution through DLL hijacking. Successful exploitation requires local access and considerable technical complexity, though the vendor has not provided a patch despite early disclosure notification. This vulnerability carries a high impact rating with potential for complete system compromise (confidentiality, integrity, and availability). | MEDIUM | 6.4 | 0.0% | 32 |
No patch
|