How severe is CVE-2023-46239?

CVE-2023-46239 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-2023-46239 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-46239?

CVE-2023-46239 affects Quic-go Project Quic-go. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-46239?

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-2023-46239 published?

CVE-2023-46239 was published on 2023-10-31 and last updated on 2026-06-17.

CVE-2023-46239

CVE-2023-46239 is a high-severity vulnerability in Quic-go Project Quic-go 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-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Quic-go Project Quic-go
Published: 2023-10-31
Last modified: 2026-06-17

Description

quic-go is an implementation of the QUIC protocol in Go. Starting in version 0.37.0 and prior to version 0.37.3, by serializing an ACK frame after the CRYTPO that allows a node to complete the handshake, a remote node could trigger a nil pointer dereference (leading to a panic) when the node attempted to drop the Handshake packet number space. An attacker can bring down a quic-go node with very minimal effort. Completing the QUIC handshake only requires sending and receiving a few packets. Version 0.37.3 contains a patch. Versions before 0.37.0 are not affected.

Frequently asked questions

What is CVE-2023-46239?: quic-go is an implementation of the QUIC protocol in Go. Starting in version 0.37.0 and prior to version 0.37.3, by serializing an ACK frame after the CRYTPO that allows a node to complete the handshake, a remote node could trigger a nil pointer dereference (leading to a panic) when the node attempted to drop the Handshake packet number space. An attacker can bring down a quic-go node with very minimal effort. Completing the QUIC handshake only requires sending and receiving a few packets. Version 0.37.3 contains a patch. Versions before 0.37.0 are not affected.
How severe is CVE-2023-46239?: CVE-2023-46239 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-2023-46239 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-46239?: CVE-2023-46239 affects Quic-go Project Quic-go. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-46239?: 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-2023-46239 published?: CVE-2023-46239 was published on 2023-10-31 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:quic-go_project:quic-go:*:*:*:*:*:*:*:*

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