Vulnerability · Published Jul 29, 2026 · Assigned by apache
CVE-2026-58155Apache Traffic Server: Header-name length truncation enables header aliasing and request smuggling
Critical 9.3
In plain English
A critical-severity security flaw in Apache Traffic Server from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities).
Severity (CVSS 3.1)9.3Critical
Exploit odds (30 days)0.5%top 54.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Apache Traffic Server truncates over-long header names, allowing header aliasing, request smuggling, and policy bypass. 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | trafficserver | no fix listed | DEBIAN-CVE-2026-58155 |
| Ubuntu:24.04:LTS | trafficserver | no fix listed | UBUNTU-CVE-2026-58155 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache Traffic Server | 8.0.0 – through 8.1.119.0.0 – through 9.2.1410.0.0 – through 10.1.3 |
Weakness: CWE-444 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N
References
- https://lists.apache.org/thread/5prl9glcm9g2swnq9hqxvnokylm1gr6d vendor-advisory