How severe is CVE-2025-48954?

CVE-2025-48954 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2025-48954 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-48954?

CVE-2025-48954 primarily affects Discourse. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-48954?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-48954 have an EU (EUVD) identifier?

Yes. CVE-2025-48954 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-28274.

When was CVE-2025-48954 published?

CVE-2025-48954 was published on 2025-06-25 and last updated on 2026-06-17.

CVE-2025-48954

CVE-2025-48954 is a high-severity vulnerability in Discourse with a CVSS 3.x base score of 8.1. 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: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-28274
Weakness: CWE-79
Affected product: Discourse
Published: 2025-06-25
Last modified: 2026-06-17

Description

Discourse is an open-source discussion platform. Versions prior to 3.5.0.beta6 are vulnerable to cross-site scripting when the content security policy isn't enabled when using social logins. Version 3.5.0.beta6 patches the issue. As a workaround, have the content security policy enabled.

Frequently asked questions

What is CVE-2025-48954?: Discourse is an open-source discussion platform. Versions prior to 3.5.0.beta6 are vulnerable to cross-site scripting when the content security policy isn't enabled when using social logins. Version 3.5.0.beta6 patches the issue. As a workaround, have the content security policy enabled.
How severe is CVE-2025-48954?: CVE-2025-48954 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2025-48954 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-48954?: CVE-2025-48954 primarily affects Discourse. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-48954?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-48954 have an EU (EUVD) identifier?: Yes. CVE-2025-48954 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-28274.
When was CVE-2025-48954 published?: CVE-2025-48954 was published on 2025-06-25 and last updated on 2026-06-17.

References

https://github.com/discourse/discourse/security/advisories/GHSA-26p5-mjjh-wfcf

Affected products (6)

cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:*
cpe:2.3:a:discourse:discourse:3.5.0:beta1:*:*:beta:*:*:*
cpe:2.3:a:discourse:discourse:3.5.0:beta2:*:*:beta:*:*:*
cpe:2.3:a:discourse:discourse:3.5.0:beta3:*:*:beta:*:*:*
cpe:2.3:a:discourse:discourse:3.5.0:beta4:*:*:beta:*:*:*
cpe:2.3:a:discourse:discourse:3.5.0:beta5:*:*:beta:*:*:*

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