How severe is CVE-2024-39305?

CVE-2024-39305 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 none, and availability low.

Is CVE-2024-39305 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-39305?

CVE-2024-39305 primarily affects Envoyproxy Envoy. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-39305?

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

Does CVE-2024-39305 have an EU (EUVD) identifier?

Yes. CVE-2024-39305 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-37891.

When was CVE-2024-39305 published?

CVE-2024-39305 was published on 2024-07-01 and last updated on 2026-06-17.

CVE-2024-39305

CVE-2024-39305 is a medium-severity vulnerability in Envoyproxy Envoy 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-416.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-37891
Weakness: CWE-416
Affected product: Envoyproxy Envoy
Published: 2024-07-01
Last modified: 2026-06-17

Description

Envoy is a cloud-native, open source edge and service proxy. Prior to versions 1.30.4, 1.29.7, 1.28.5, and 1.27.7. Envoy references already freed memory when route hash policy is configured with cookie attributes. Note that this vulnerability has been fixed in the open as the effect would be immediately apparent if it was configured. Memory allocated for holding attribute values is freed after configuration was parsed. During request processing Envoy will attempt to copy content of de-allocated memory into request cookie header. This can lead to arbitrary content of Envoy's memory to be sent to the upstream service or abnormal process termination. This vulnerability is fixed in Envoy versions v1.30.4, v1.29.7, v1.28.5, and v1.27.7. As a workaround, do not use cookie attributes in route action hash policy.

Frequently asked questions

What is CVE-2024-39305?: Envoy is a cloud-native, open source edge and service proxy. Prior to versions 1.30.4, 1.29.7, 1.28.5, and 1.27.7. Envoy references already freed memory when route hash policy is configured with cookie attributes. Note that this vulnerability has been fixed in the open as the effect would be immediately apparent if it was configured. Memory allocated for holding attribute values is freed after configuration was parsed. During request processing Envoy will attempt to copy content of de-allocated memory into request cookie header. This can lead to arbitrary content of Envoy's memory to be sent to the upstream service or abnormal process termination. This vulnerability is fixed in Envoy versions v1.30.4, v1.29.7, v1.28.5, and v1.27.7. As a workaround, do not use cookie attributes in route action hash policy.
How severe is CVE-2024-39305?: CVE-2024-39305 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 none, and availability low.
Is CVE-2024-39305 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-39305?: CVE-2024-39305 primarily affects Envoyproxy Envoy. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-39305?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-39305 have an EU (EUVD) identifier?: Yes. CVE-2024-39305 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-37891.
When was CVE-2024-39305 published?: CVE-2024-39305 was published on 2024-07-01 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:envoyproxy:envoy:1.27.6:*:*:*:*:*:*:*
cpe:2.3:a:envoyproxy:envoy:1.28.4:*:*:*:*:*:*:*
cpe:2.3:a:envoyproxy:envoy:1.29.6:*:*:*:*:*:*:*
cpe:2.3:a:envoyproxy:envoy:1.30.3:*:*:*:*:*:*:*

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