Critical Memory corruption

CVE-2026-42369 — GV-VMS V20 Stack Buffer Overflow in WebCam Server via Base64 Decoding (CWE-787)

GV-VMS V20 is a Video Monitoring Software used to gather the feeds of many surveillance cameras and manage other security devices. It is a native application accessed locally, but it is also possible to enable remote access via the "WebCam Server" feature. Once enabled, it is possible to access to the management and monitoring feature via a regular Web interface. This webersever is another native application, compiled without ASLR, which makes exploitation much easier and more likely. Most of the features require authentication before being reachable and leverage a standard login page to grant access. However the `gvapi` endpoint uses its own authentication mechanism via an `HTTP Authorization` header. It supports both `Basic` authentication and the `Digest` modes of authentication. #### Stack-overflow via unbound copy of base64 decoded string The `b64decoder` string is sized dynamically, but it is then copied to the `Buffer` stack variable one character at the time at [0], and there's no bound-check. As such, if the decoded string is bigger than 256 characters (the size of the `Buffer` variable) then a stack overflow occurs. Because the data can be fully controlled by an attacker and lack of ASLR, this vulnerability can easily be exploited to gain full code execution as SYSTEM on the machine running the service.

Published May 3, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GV

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.9% (30-day exploitation probability)+9
Technical severity (critical)+10
Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.87%

ahead of 58% of scored CVEs · Oct 14, 2026

Affects

Geovision

GV-VMS V20.0.2

CVSS base

10.0

Critical · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

Yes

can an attacker script the kill-chain steps

Technical impact

Total

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Geovision GV-VMS V20.0.2).
The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Geovision	GV-VMS V20.0.2	version V20.0.2	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

None

User interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
10.0	CVSS 3.1	Critical	3.9	6.0	0df08a0e-a200-4957-9bb0-084f562506f9 via NIST National Vulnerability Database
10.0	CVSS 3.1	Critical	—	—	GV via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H (score shown at the top: 0df08a0e-a200-4957-9bb0-084f562506f9)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-787 · Out-of-bounds Write

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.87%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.

web/proxy/WAF logsnetwork IDS/IPSendpoint telemetry (EDR)crash dumps

Analysis and videos

CVE-2026-42369: GV-VMS V20 Stack Buffer Overflow in WebCam Server via Base64 Decoding (CWE-787)
CVE-2026-42369 is a stack-based buffer overflow (CWE-787) in Geovision GV-VMS V20 that the CNA rates as Critical with CVSS 3.1 10.0. According to the record, the flaw is in the base64 decoding of data handled by the gvapi endpoint of the WebCam Server web interface. No fixed version, affected version range, or confirmed exploitation appears in the sources consulted.

Timeline

What happened to this CVE, newest first.

2026
Affected products added · geovision inc./gv-vms v20.0.2
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
CVSS changed · 10.0
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Deferred
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
May 3, 2026 · GV

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

www.geovision.com.tw/cyber_security.php
vendor-advisory, third-party-advisory, NIST National Vulnerability Database

Elsewhere on this site

Geovision
every CVE for this vendor

Memory corruption
same class

CWE-787
other pages naming this weakness

Related CVEs (same products)

Critical CVE-2026-7372 GeoVision GV-VMS V20 WebCam Server Login stack overflow vulnerability May 3, 2026
Critical CVE-2026-42370 GeoVision GV-VMS V20 WebCam Server Login stack overflow vulnerability May 3, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-42369 is "GV-VMS V20 Stack Buffer Overflow in WebCam Server via Base64 Decoding (CWE-787)", rated Critical. It affects GV-VMS V20.0.2 (Geovision); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 10.0 describes technical severity. EPSS 0.87% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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