CVE-2026-58155: apache software foundation apache traffic server HTTP Request/Response Smuggling
Vulnerability summary
CVE-2026-58155 is a critical (CVSS 9.3) HTTP Request/Response Smuggling vulnerability in apache software foundation apache traffic server. EPSS estimates a 0.54% chance of exploitation in the next 30 days, higher than 44.1% of scored vulnerabilities.
Timeline
- 29-07-2026PublishedVulnerability first disclosed.
- 01-10-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
7 scores · 4 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated9.2CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N
- OSV · DebianEcosystem advisory · calculated9.2CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- NVDNIST9.2CriticalCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated9.3CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N
- NVDNIST9.3CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N
EPSS trend
Probability
0.54%
Chance of exploitation in the next 30 days
Percentile
44%
Versus all other CVEs
30-day change
+0.13 pp
From 0.40% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Apache1 product
- traffic_server≥ 8.0.0, ≤ 8.1.9 | ≥ 9.0.0, < 9.2.15 | ≥ 10.0.0, < 10.1.4
Apache software foundation1 product
- apache traffic server≥ 8.0.0, ≤ 8.1.11 | ≥ 9.0.0, ≤ 9.2.14 | ≥ 10.0.0, ≤ 10.1.3
Debian1 product
- trafficserverAll versions (No fix recorded)
Ubuntu1 product
- trafficserverAll versions (No fix recorded)
4 vendors · 4 products