How severe is CVE-2026-65100?

CVE-2026-65100 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.

Is CVE-2026-65100 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-2026-65100?

CVE-2026-65100 affects Apache Traffic Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-65100?

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

When was CVE-2026-65100 published?

CVE-2026-65100 was published on 2026-07-29 and last updated on 2026-08-03.

CVE-2026-65100

CVE-2026-65100 is a medium-severity vulnerability in Apache Traffic Server with a CVSS 3.x base score of 4.8. 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-696.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
CVSS v4: 6.3
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-696
Affected product: Apache Traffic Server
Published: 2026-07-29
Last modified: 2026-08-03

Description

Apache Traffic Server updates the HTTP/2 HPACK dynamic table before confirming the header block encoded successfully, so an encode failure leaves the encoder out of sync with the peer decoder and corrupts subsequent header blocks on the connection. 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-2026-65100?: Apache Traffic Server updates the HTTP/2 HPACK dynamic table before confirming the header block encoded successfully, so an encode failure leaves the encoder out of sync with the peer decoder and corrupts subsequent header blocks on the connection. 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-2026-65100?: CVE-2026-65100 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability low.
Is CVE-2026-65100 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-2026-65100?: CVE-2026-65100 affects Apache Traffic Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-65100?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-65100 published?: CVE-2026-65100 was published on 2026-07-29 and last updated on 2026-08-03.

References

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

Affected products (1)

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

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