How severe is CVE-2026-43504?

CVE-2026-43504 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.

Is CVE-2026-43504 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-43504?

CVE-2026-43504 affects Prosody. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-43504?

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

Does CVE-2026-43504 have an EU (EUVD) identifier?

Yes. CVE-2026-43504 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26657.

When was CVE-2026-43504 published?

CVE-2026-43504 was published on 2026-05-01 and last updated on 2026-06-17.

CVE-2026-43504

CVE-2026-43504 is a medium-severity vulnerability in Prosody with a CVSS 3.x base score of 6.5. 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-863.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-26657
Weakness: CWE-863
Affected product: Prosody
Published: 2026-05-01
Last modified: 2026-06-17

Description

An issue was discovered in Prosody before 0.12.6 and 1.0.0 through 13.0.0 before 13.0.5, when mod_proxy65 is enabled. Because mod_proxy65 mishandles access control in a paused scenario, relaying of unauthenticated traffic can occur.

Frequently asked questions

What is CVE-2026-43504?: An issue was discovered in Prosody before 0.12.6 and 1.0.0 through 13.0.0 before 13.0.5, when mod_proxy65 is enabled. Because mod_proxy65 mishandles access control in a paused scenario, relaying of unauthenticated traffic can occur.
How severe is CVE-2026-43504?: CVE-2026-43504 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.
Is CVE-2026-43504 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-43504?: CVE-2026-43504 affects Prosody. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-43504?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-43504 have an EU (EUVD) identifier?: Yes. CVE-2026-43504 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-26657.
When was CVE-2026-43504 published?: CVE-2026-43504 was published on 2026-05-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:prosody:prosody:*:*:*:*:*:*:*:*

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