CVE-2023-38522 | Apache Traffic Server: Incomplete field name check allows request smuggling

Apache Traffic Server accepts characters that are not allowed for HTTP field names and forwards malformed requests to origin servers. This can be utilized for request smuggling and may also lead cache poisoning if the origin servers are vulnerable. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.10, from 9.0.0 through 9.2.4. Users are recommended to upgrade to version 8.1.11 or 9.2.5, which fixes the issue.

Published: 2024-07-26 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-38522 is rated Moderate Risk (50.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.99%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-38522

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.49% 0.99% +0.50%
2 2026-05-09 0.36% 0.49% +0.12%
3 2026-04-01 — 0.36% —

Full EPSS history (25 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-38522

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2023-38522

OS Trackers for CVE-2023-38522

vendor priority summary link
debian not yet assigned CVE-2023-38522 not yet assigned priority: Debian including 1 source packages (trafficserver), 3 status rows across 3 suites (bookworm, bullseye, sid): resolved 3. https://security-tracker.debian.org/tracker/CVE-2023-38522
ubuntu medium CVE-2023-38522 medium priority: Ubuntu including 1 source packages (trafficserver), 9 status rows across 9 suites (bionic, focal, jammy, noble, oracular, plucky, questing, upstream, xenial): needed 3, ignored 2, needs-triage 2, not-affected 1, released 1. https://ubuntu.com/security/CVE-2023-38522

Affected software / configurations for CVE-2023-38522

Vendor Product Version Raw CPE
apache traffic_server >= 8.0.0, < 8.1.11 cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*
apache traffic_server >= 9.0.0, < 9.2.5 cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*

References for CVE-2023-38522

cvelogic Threat Intelligence