How severe is CVE-2026-39823?

CVE-2026-39823 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-39823 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-39823?

CVE-2026-39823 affects Golang Go. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39823?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-39823 have an EU (EUVD) identifier?

Yes. CVE-2026-39823 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28424.

When was CVE-2026-39823 published?

CVE-2026-39823 was published on 2026-05-07 and last updated on 2026-06-17.

CVE-2026-39823

CVE-2026-39823 is a medium-severity vulnerability in Golang Go with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-28424
Weakness: CWE-79
Affected product: Golang Go
Published: 2026-05-07
Last modified: 2026-06-17

Description

CVE-2026-27142 fixed a vulnerability in which URLs were not correctly escaped inside of a <meta> tag's <content> attribute. If the URL content were to insert ASCII whitespaces around the '=' rune inside of the <content> attribute, the escaper would fail to similarly escape it, leading to XSS.

Frequently asked questions

What is CVE-2026-39823?: CVE-2026-27142 fixed a vulnerability in which URLs were not correctly escaped inside of a <meta> tag's <content> attribute. If the URL content were to insert ASCII whitespaces around the '=' rune inside of the <content> attribute, the escaper would fail to similarly escape it, leading to XSS.
How severe is CVE-2026-39823?: CVE-2026-39823 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-39823 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-39823?: CVE-2026-39823 affects Golang Go. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39823?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-39823 have an EU (EUVD) identifier?: Yes. CVE-2026-39823 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28424.
When was CVE-2026-39823 published?: CVE-2026-39823 was published on 2026-05-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*

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