Critical severity · published Oct 21, 2026
CVE-2026-111816
Apache Traffic Server: A malformed 302 response bypasses parse-error rejection through the Transfer-Encoding: chunked carve-out
New
9.3
CVSS
0.3%
EPSS
No
On KEV
Description
Apache Traffic Server forwarded a malformed 302 response that should have been rejected as a parse error, because the Transfer-Encoding: chunked carve-out bypassed the rejection path. A response that two peers can read differently is then stored and served, allowing cache poisoning and response-framing desync.
This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0.
Users are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
High
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 24% 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 9.2.15; 10.0.0 through 10.1.4; 10.2.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-111816
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-111816
lists.apache.org
https://lists.apache.org/thread/r95dq29ywcd1f4x30snxlqmb12z4s4kc
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