CVE-2026-53839

Q: How do I fix CVE-2026-53839?

Upgrade openclaw to 2026.5.7 or later.

Q: Is CVE-2026-53839 being actively exploited?

Not that we know of. CVE-2026-53839 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.27% is the estimated probability that it will be exploited in the next 30 days. That is higher than 18% of all scored CVEs.

Q: How severe is CVE-2026-53839?

CVE-2026-53839 has a CVSS v3 base score of 6.5, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

Q: What does CVE-2026-53839 affect?

Published advisories record a fix for openclaw (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

MEDIUM

6.5

CVSS v3

NVD

Description

OpenClaw before 2026.5.7 contains a hostname validation vulnerability in retry endpoint checks that allows matching hostname prefixes instead of exact hostnames. Attackers can exploit this by crafting a hostname prefix resembling a trusted host to send authentication material to untrusted endpoints.

CWE-1023

How to fix

Remediation Available

openclawNVD

Affected:< 2026.5.7Fixed in:2026.5.7CVE-2026-53839derived from NVD

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

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 RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityNone

AvailabilityNone

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

Exploit Intelligence

0.27%probability of exploitation in 30 days

18thpercentile

Low risk: more likely to be exploited than 18% of all known CVEs.

References

Vendor Advisory1

github.com

Third-Party Advisory1

vulncheck.com

Related Vulnerabilities

Other CWE-1023 vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2026-7473	Medium	5.8	1.1%	KEV	-
CVE-2021-23146	High	7.1	0.9%	-	Fix
CVE-2025-55333	High	6.1	0.8%	-	Fix
CVE-2026-4599	Critical	9.1	0.5%	-	Fix
CVE-2024-5528	Low	3.5	0.4%	-	Fix
CVE-2026-24255	High	7.5	0.4%	-	-

Common questions

How do I fix CVE-2026-53839?

Upgrade openclaw to 2026.5.7 or later.

Is CVE-2026-53839 being actively exploited?

Not that we know of. CVE-2026-53839 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.27% is the estimated probability that it will be exploited in the next 30 days. That is higher than 18% of all scored CVEs.

How severe is CVE-2026-53839?

CVE-2026-53839 has a CVSS v3 base score of 6.5, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2026-53839 affect?

Published advisories record a fix for openclaw (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2026-53839

Markdown

[![CVE-2026-53839](https://tridentstack.com/cve/badge/CVE-2026-53839.svg)](https://tridentstack.com/cve/CVE-2026-53839)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-53839"><img src="https://tridentstack.com/cve/badge/CVE-2026-53839.svg" alt="CVE-2026-53839"></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.

See how it works Start freeThis CVE lookup is free and always will be.

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 2026-07-23.