Apache Traffic Server vulnerabilities

Apache Traffic Server before 6.2.1 generates a coredump when there is a mismatch between content length and chunked encoding.

Apache Traffic Server versions 6.0.0 to 6.2.0 are affected by an HPACK Bomb Attack.

Unspecified vulnerability in Apache Traffic Server versions 3.x through 3.2.5, 4.x before 4.2.1.1, and 5.x before 5.0.1. This vulnerability may be related to health checks, but its impact and attack vectors are unknown.

Apache Traffic Server contains an improper access control vulnerability. This issue affects Apache Traffic Server from 9.0.0 through 9.2.14 and from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fixes the issue. This CVE supersedes CVE-2026-41920, whose record listed the affected 9.x versions as 9.0.0 through 9.1.14 and the fixed version as 9.1.15; all 9.2.x releases before 9.2.15 are affected.

The Apache Traffic Server certifier plugin generates certificates based on attacker-controlled client SNI. This issue affects Apache Traffic Server versions from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.14, and from 10.0.0 through 10.1.3.

Apache Traffic Server truncates over-long header names, allowing header aliasing, request smuggling, and policy bypass. This issue affects versions 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3.

Apache Traffic Server does not reject Transfer-Encoding in HTTP/2 requests, allowing downgrade request smuggling. This issue affects versions 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3.

Apache Traffic Server allows request smuggling when chunked messages are malformed. This issue affects versions 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3.

Apache Traffic Server has an Improper Access Control vulnerability. This affects versions from 9.0.0 to 9.1.14 and from 10.0.0 to 10.1.3.

Apache Traffic Server has an Improper Input Validation vulnerability. This affects versions from 9.2.0 to 9.2.14 and from 10.1.0 to 10.1.3.

Improper Input Validation vulnerability in Apache Traffic Server. This issue affects Apache Traffic Server through version 9.2.1.

The HTTP/2 experimental feature in Apache Traffic Server 5.3.x before 5.3.1 allows remote attackers to cause a denial of service (out-of-bounds access and daemon crash) or possibly execute arbitrary code via vectors related to the frame_handlers array or set_dynamic_table_size function.

Apache Traffic Server 5.1.x before 5.1.1 allows remote attackers to bypass access restrictions by leveraging failure to properly tunnel remap requests using CONNECT.

An unspecified vulnerability in the HTTP/2 experimental feature in Apache Traffic Server before version 5.3.2 may lead to unknown impact and attack vectors.

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 8.1.11, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3.

Apache Traffic Server allows redirect-limit bypass when plugins reset the retry counter, enabling SSRF amplification. This affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3. Users are recommended to upgrade to 9.2.15 or 10.1.4.

Several Apache Traffic Server experimental plugins have memory-safety and limit-bypass errors. 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.

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 8.1.11, 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.

The Apache Traffic Server webp_transform plugin can decode unsafely and serve mislabeled, cacheable responses. 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.

The Apache Traffic Server intercept plugin has a use-after-free. 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.

The header_rewrite plugin in Apache Traffic Server can crash or corrupt memory during cookie operations and CIDR condition matching. This affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3. Users are recommended to upgrade to 9.2.15 or 10.1.4.

The Apache Traffic Server prefetch plugin can crash when processing attacker-influenced input. 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.

The Apache Traffic Server ts_lua plugin mishandles initialization, transform context, and per-instance state. 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.

The Apache Traffic Server uri_signing and url_sig plugins can exhaust the stack or crash on attacker input. 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.

The Apache Traffic Server txn_box plugin overflows the stack from attacker-controlled input. 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.

The regex_remap plugin in Apache Traffic Server overflows the stack and integers from substitution input. This affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3. Users are recommended to upgrade to 9.2.15 or 10.1.4.

The Apache Traffic Server ESI plugin can recurse without bound and fetch attacker-controlled URLs. 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.

The Cripts framework of Apache Traffic Server has out-of-bounds writes, path traversal, and use-after-free errors. Affected versions: 10.0.0 through 10.1.3.

Apache Traffic Server leaks memory when handling HostDB SRV records. 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.

Apache Traffic Server has use-after-free and time-of-check/time-of-use errors in remap configuration handling. This affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3. Users are recommended to upgrade to 9.2.15 or 10.1.4.

Apache Traffic Server mishandles on-disk cache fields and object lifetimes, corrupting state or crashing. 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.

Apache Traffic Server can crash from null dereferences and dangling references in TLS and SNI handling. This affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3. Users are recommended to upgrade to 9.2.15 or 10.1.4.

Apache Traffic Server reads out of bounds while parsing DNS answers. 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.

Apache Traffic Server can bypass IP access controls on UDS listeners and through ACL matching errors. This affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3. Users are recommended to upgrade to 9.2.15 or 10.1.4.

Apache Traffic Server mishandles PROXY protocol input, truncating ports and overflowing the stack. Affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3.

Apache Traffic Server can reuse server sessions and tunnels improperly, exposing data across client connections. Affected versions are from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.14, and from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4.

Apache Traffic Server reuses multiplexed HTTP/2 origin connections without verifying that the server certificate covers the new request hostname. This affects versions from 9.0.0 through 9.2.14 and from 10.0.0 through 10.1.3.

Apache Traffic Server drops the per-stream buffer cap when dechunking HTTP/2 or HTTP/3 responses, letting a slow client exhaust server memory. This affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3. Users are recommended to upgrade to 9.2.15 or 10.1.4.

Apache Traffic Server mis-parses ports in URLs and userinfo, allowing port-based access-control bypass. Affects versions from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.14, and from 10.0.0 through 10.1.3.

Apache Traffic Server can write out of bounds or overflow integers while parsing MIME and HTTP headers. Affected versions are from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.14, and from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4.

Apache Traffic Server forwards HTTP/2 origin trailers to HTTP/1 clients without proper chunked framing when converting HTTP/2 to HTTP/1. Affects versions 10.0.0 through 10.1.3.

Apache Traffic Server mishandles integers while decoding HPACK/XPACK headers, corrupting memory. Affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3.

Apache Traffic Server can be crashed or driven to resource exhaustion by abusive HTTP/2 framing and flow-control. Affected versions are from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.14, and from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4.

Apache Traffic Server copies the client Host header into a fixed-size stack buffer without a bound during redirect handling, causing a stack overflow when redirect following is enabled. Affects versions from 8.0.0 through 8.1.11, 9.0.0 through 9.2.14, and 10.0.0 through 10.1.3.

HTTP Request Smuggling vulnerability in Apache Traffic Server. Affects versions 10.0.0 through 10.1.3 and 9.0.0 through 9.2.14.

A Regular Expression without Anchors vulnerability was found in Apache Traffic Server. It affects versions from 10.0.X through 10.1.3 and from 9.0.X through 9.2.14. Upgrading to version 9.2.15 or 10.1.4 fixes the issue.

Uncontrolled resource consumption vulnerability in Apache Traffic Server. Affects versions from 9.0.0 through 9.1.13 and from 10.0.0 through 10.1.2.

A vulnerability in Apache Traffic Server (versions 9.0.0 through 9.2.12 and 10.0.0 through 10.1.1) allows request smuggling if chunked messages are malformed.

A bug in POST request handling causes a crash under a certain condition in Apache Traffic Server versions 10.0.0 through 10.1.1 and 9.0.0 through 9.2.12. The issue is fixed in versions 10.1.2 and 9.2.13. A workaround for older versions is to set proxy.config.http.request_buffer_enabled to 0.

A vulnerability in Apache Traffic Server allows unauthorized exposure of sensitive information. This affects versions from 8.0.0 through 9.2.0.