CVE-2024-38475 | Apache HTTP Server weakness in mod_rewrite when first segment of substitution matches filesystem path.

Exp

Improper escaping of output in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to map URLs to filesystem locations that are permitted to be served by the server but are not intentionally/directly reachable by any URL, resulting in code execution or source code disclosure. Substitutions in server context that use a backreferences or variables as the first segment of the substitution are affected.  Some unsafe RewiteRules will be broken by this change and the rewrite flag "UnsafePrefixStat" can be used to opt back in once ensuring the substitution is appropriately constrained.

Published: 2024-07-01 Last update: 2025-11-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-38475 is rated Critical Active Threat (96.4/100): CVSS Critical severity, with high exploitation likelihood (EPSS 93.86%, 100th percentile). CISA KEV confirms active exploitation (added 2025-05-01) affecting Apache / HTTP Server. a weakness (CWE-116) Unauthenticated remote administrative access may be possible. The CISA remediation deadline has passed—treat as an emergency patch priority.

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

CISA KEV Record for CVE-2024-38475

Name: Apache HTTP Server Improper Escaping of Output Vulnerability · CISA KEV detail

Exploit added: 2025-05-01

Action due: 2025-05-22

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Exploit prediction scoring system (EPSS) score for CVE-2024-38475

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 2026-05-10 93.78% 93.86% +0.08%
2 2026-05-01 93.37% 93.78% +0.41%
3 2026-04-26 — 93.37% —

Full EPSS history (51 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-38475

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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:H)
Serious risk that confidential data gets exposed in a big 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 5.2 [email protected]
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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:H)
Serious risk that confidential data gets exposed in a big 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 5.2 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2024-38475

OS Trackers for CVE-2024-38475

vendor priority summary link
alpine — CVE-2024-38475: 1 source package rows (apache2); 7 state rows across 7 repos (3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 7, open 0. https://security.alpinelinux.org/vuln/CVE-2024-38475
debian not yet assigned CVE-2024-38475 not yet assigned priority: Debian including 1 source packages (apache2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2024-38475
gentoo low CVE-2024-38475: 1 GLSA(s) (202409-31), 1 atom(s) (www-servers/apache); latest impact low. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2024-38475
redhat high — https://access.redhat.com/security/cve/CVE-2024-38475
suse high CVE-2024-38475 severity important: SUSE including 323 source package names (2.8:apache2-utils-2.4.58-150600.5.18.1, 4.3.13.9.57.7:apache2-2.4.51-150400.6.29.1, …), 540 product×package rows across 77 product lines (Container bci/php-apache, Container suse/manager/4.3/proxy-httpd, … (77 product lines)): Fixed 309, Known Affected 231. https://www.suse.com/security/cve/CVE-2024-38475/
ubuntu high CVE-2024-38475 high priority: Ubuntu including 1 source packages (apache2), 10 status rows across 10 suites (bionic, focal, jammy, mantic, noble, oracular, plucky, trusty, upstream, xenial): released 10. https://ubuntu.com/security/CVE-2024-38475

Affected software / configurations for CVE-2024-38475

Vendor Product Version Raw CPE
apache http_server >= 2.4.0, < 2.4.60 cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
netapp ontap_9 — cpe:2.3:a:netapp:ontap_9:-:*:*:*:*:*:*:*
sonicwall sma_200_firmware < 10.2.1.14-75sv cpe:2.3:o:sonicwall:sma_200_firmware:*:*:*:*:*:*:*:*
sonicwall sma_210_firmware < 10.2.1.14-75sv cpe:2.3:o:sonicwall:sma_210_firmware:*:*:*:*:*:*:*:*
sonicwall sma_400_firmware < 10.2.1.14-75sv cpe:2.3:o:sonicwall:sma_400_firmware:*:*:*:*:*:*:*:*
sonicwall sma_410_firmware < 10.2.1.14-75sv cpe:2.3:o:sonicwall:sma_410_firmware:*:*:*:*:*:*:*:*
sonicwall sma_500v_firmware < 10.2.1.14-75sv cpe:2.3:o:sonicwall:sma_500v_firmware:*:*:*:*:*:*:*:*

References for CVE-2024-38475

cvelogic Threat Intelligence