Critical severity · published Jul 29, 2026
CVE-2026-57834
Apache Traffic Server: Malformed chunked message body allows request smuggling
10.0
CVSS
0.6%
EPSS
No
On KEV
Description
Apache Traffic Server allows request smuggling if chunked messages are malformed.
This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, 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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AT
Apache Traffic Server · Apache Software Foundation
8.0.0 through 8.1.11; 9.0.0 through 9.2.14; 10.0.0 through 10.1.3 · source: vendor
TS
Traffic Server · Apache
8.0.0 through 8.1.9; 9.0.0 before 9.2.15; 10.0.0 before 10.1.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-57834
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-57834
vendor-advisory
https://lists.apache.org/thread/5prl9glcm9g2swnq9hqxvnokylm1gr6d
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