How severe is CVE-2026-56277?

CVE-2026-56277 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 low, integrity low, and availability none.

Is CVE-2026-56277 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-56277?

CVE-2026-56277 affects Flowiseai Flowise. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-56277?

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

When was CVE-2026-56277 published?

CVE-2026-56277 was published on 2026-06-30 and last updated on 2026-07-06.

CVE-2026-56277

CVE-2026-56277 is a medium-severity vulnerability in Flowiseai Flowise 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-346.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 6.9
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-346
Affected product: Flowiseai Flowise
Published: 2026-06-30
Last modified: 2026-07-06

Description

Flowise before 3.1.2 sets Access-Control-Allow-Origin to a hardcoded wildcard (*) on its text-to-speech (TTS) generation endpoint (packages/server/src/controllers/text-to-speech/index.ts), independent of the server's configured CORS policy. This bypasses the server's otherwise restrictive default CORS configuration (getCorsOptions()) and allows any webpage to make cross-origin requests that trigger TTS generation using stored credentials, enabling drive-by cross-origin credential abuse.

Frequently asked questions

What is CVE-2026-56277?: Flowise before 3.1.2 sets Access-Control-Allow-Origin to a hardcoded wildcard (*) on its text-to-speech (TTS) generation endpoint (packages/server/src/controllers/text-to-speech/index.ts), independent of the server's configured CORS policy. This bypasses the server's otherwise restrictive default CORS configuration (getCorsOptions()) and allows any webpage to make cross-origin requests that trigger TTS generation using stored credentials, enabling drive-by cross-origin credential abuse.
How severe is CVE-2026-56277?: CVE-2026-56277 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 low, integrity low, and availability none.
Is CVE-2026-56277 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-56277?: CVE-2026-56277 affects Flowiseai Flowise. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-56277?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-56277 published?: CVE-2026-56277 was published on 2026-06-30 and last updated on 2026-07-06.

References

Affected products (1)

cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

18.228.228.159 (ipv4-addr)
3.19.213.118 (ipv4-addr)
51.17.154.141 (ipv4-addr)