Is CVE-2026-34839 in the CISA KEV catalog?

No. CVE-2026-34839 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-34839?

CVE-2026-34839 has a CVSS v3 base score of 6.5 (MEDIUM).

What is the EPSS score for CVE-2026-34839?

CVE-2026-34839 has an EPSS score of 0.41% (33th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2026-34839?

Upgrade glances on debian unstable to 4.5.4+dfsg-1 or later.

CVE & CISA-KEV Catalog

CVE-2026-34839

MEDIUM

6.5

CVSS v3

NVD

Description

Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.4, the Glances web server exposes a REST API (`/api/4/*`) that is accessible without authentication and allows cross-origin requests from any origin due to a permissive CORS policy (`Access-Control-Allow-Origin: *`). This allows a malicious website to read sensitive system information from a running Glances instance in the victim’s browser, leading to cross-origin data exfiltration. While a previous advisory exists for XML-RPC CORS issues, this report demonstrates that the REST API (`/api/4/*`) is also affected and exposes significantly more sensitive data. Version 4.5.4 patches the issue.

CWE-200Information Exposure CWE-306Missing Authentication for Critical Function CWE-942

How to fix

Remediation Available

glancesDebian

Fixed in:4.5.4+dfsg-1CVE-2026-34839

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionRequired

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityNone

AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Exploit Intelligence

0.41%probability of exploitation in 30 days

33rdpercentile

Low risk: more likely to be exploited than 33% of all known CVEs.

References

Patch1

github.com

Exploit1

github.com

Embed a live status badge for CVE-2026-34839

Markdown

[![CVE-2026-34839](https://tridentstack.com/cve/badge/CVE-2026-34839.svg)](https://tridentstack.com/cve/CVE-2026-34839)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-34839"><img src="https://tridentstack.com/cve/badge/CVE-2026-34839.svg" alt="CVE-2026-34839"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-24.