How severe is CVE-2024-31309?

CVE-2024-31309 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-2024-31309 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 95% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-31309?

CVE-2024-31309 primarily affects Apache Traffic Server. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-31309?

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.

Does CVE-2024-31309 have an EU (EUVD) identifier?

Yes. CVE-2024-31309 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-29205.

When was CVE-2024-31309 published?

CVE-2024-31309 was published on 2024-04-10 and last updated on 2026-06-17.

CVE-2024-31309

CVE-2024-31309 is a high-severity vulnerability in Apache Traffic Server with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 95% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 95% (100th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-29205
Weakness: CWE-20
Affected product: Apache Traffic Server
Published: 2024-04-10
Last modified: 2026-06-17

Description

HTTP/2 CONTINUATION DoS attack can cause Apache Traffic Server to consume more resources on the server. Version from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.3 are affected. Users can set a new setting (proxy.config.http2.max_continuation_frames_per_minute) to limit the number of CONTINUATION frames per minute. ATS does have a fixed amount of memory a request can use and ATS adheres to these limits in previous releases. Users are recommended to upgrade to versions 8.1.10 or 9.2.4 which fixes the issue.

Frequently asked questions

What is CVE-2024-31309?: HTTP/2 CONTINUATION DoS attack can cause Apache Traffic Server to consume more resources on the server. Version from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.3 are affected. Users can set a new setting (proxy.config.http2.max_continuation_frames_per_minute) to limit the number of CONTINUATION frames per minute. ATS does have a fixed amount of memory a request can use and ATS adheres to these limits in previous releases. Users are recommended to upgrade to versions 8.1.10 or 9.2.4 which fixes the issue.
How severe is CVE-2024-31309?: CVE-2024-31309 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-2024-31309 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 95% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-31309?: CVE-2024-31309 primarily affects Apache Traffic Server. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-31309?: 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.
Does CVE-2024-31309 have an EU (EUVD) identifier?: Yes. CVE-2024-31309 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-29205.
When was CVE-2024-31309 published?: CVE-2024-31309 was published on 2024-04-10 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:40:*:*:*:*:*:*:*

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