How severe is CVE-2026-58187?

CVE-2026-58187 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-58187 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-58187?

CVE-2026-58187 affects Apache Traffic Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-58187?

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

When was CVE-2026-58187 published?

CVE-2026-58187 was published on 2026-07-29 and last updated on 2026-07-31.

CVE-2026-58187

CVE-2026-58187 is a low-severity vulnerability in Apache Traffic Server with a CVSS 3.x base score of 3.7. 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-787.

Key facts

Severity: Low (CVSS 3.x base score 3.7)
CVSS v4: 6.3
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Apache Traffic Server
Published: 2026-07-29
Last modified: 2026-07-31

Description

The Apache Traffic Server multiplexer plugin overruns its chunk-decode buffer on upstream input, enabling denial of service. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.

Frequently asked questions

What is CVE-2026-58187?: The Apache Traffic Server multiplexer plugin overruns its chunk-decode buffer on upstream input, enabling denial of service. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.
How severe is CVE-2026-58187?: CVE-2026-58187 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-58187 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-58187?: CVE-2026-58187 affects Apache Traffic Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-58187?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-58187 published?: CVE-2026-58187 was published on 2026-07-29 and last updated on 2026-07-31.

References

https://lists.apache.org/thread/5prl9glcm9g2swnq9hqxvnokylm1gr6d

Affected products (1)

cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*

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