How severe is CVE-2026-54465?

CVE-2026-54465 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-54465 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-54465?

CVE-2026-54465 affects Faye Websocket-driver. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-54465?

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.

When was CVE-2026-54465 published?

CVE-2026-54465 was published on 2026-07-17 and last updated on 2026-08-06.

CVE-2026-54465

CVE-2026-54465 is a high-severity vulnerability in Faye Websocket-driver with a CVSS 3.x base score of 7.5. 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-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 6.3
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: Faye Websocket-driver
Published: 2026-07-17
Last modified: 2026-08-06

Description

websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.8.1, when websocket-driver is used to implement a WebSocket server on top of a TCP server using WebSocket::Driver.server() or to complement a WebSocket client, a peer can make a single connection consume an unbounded amount of memory by sending an HTTP request or response with a never-ending list of headers. This can lead to the receiving process running out of memory. This issue is fixed in version 0.8.1.

Frequently asked questions

What is CVE-2026-54465?: websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.8.1, when websocket-driver is used to implement a WebSocket server on top of a TCP server using WebSocket::Driver.server() or to complement a WebSocket client, a peer can make a single connection consume an unbounded amount of memory by sending an HTTP request or response with a never-ending list of headers. This can lead to the receiving process running out of memory. This issue is fixed in version 0.8.1.
How severe is CVE-2026-54465?: CVE-2026-54465 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-54465 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-54465?: CVE-2026-54465 affects Faye Websocket-driver. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-54465?: 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.
When was CVE-2026-54465 published?: CVE-2026-54465 was published on 2026-07-17 and last updated on 2026-08-06.

References

Affected products (1)

cpe:2.3:a:faye:websocket-driver:*:*:*:*:*:ruby:*:*

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