What is CVE-2024-38475?

CVE-2024-38475 is Apache HTTP Server weakness in mod_rewrite when first segment of substitution matches filesystem path. The supplied enrichment data classifies it as Unclassified mapped to CWE-116 CWE-116.

Which versions are affected?

Affected product and version evidence is listed in the product table above. Current public advisories should be checked for exact version scope before patch targeting is finalized.

Is there active exploitation?

Yes: CISA KEV signal present. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

Is there a public exploit?

31 public PoC repositories reported; 2 marked weaponized in current dataset. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with web/proxy/WAF logs, application logs, network IDS/IPS where available. Look for vulnerability-class behavior, product errors, suspicious authentication events, exploit probes, and abnormal process activity based only on evidence that applies to the affected product.

How should teams prioritize it?

Prioritize CVE-2024-38475 using CVSS 9.1, EPSS 100%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

The supplied mitigation guidance says to apply vendor patches and restrict external exposure until fixed. Fixed-version evidence is listed in the mitigation section above.

Which threat actors are linked publicly?

Publicly linked actor or ransomware signals in the supplied enrichment data: Mana Team (), Lucky Cat (), Red October (), Hacking Team (), UNC6148 (). Do not attribute exploitation to a threat actor unless the source evidence explicitly supports that linkage.

What should be done in the next 24 hours?

Identify exposed assets running affected vendor/product/version combinations. Treat as emergency remediation because CISA KEV status is present. Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class. Open remediation tickets with affected assets, owners, evidence status, and detection coverage so decisions are traceable.

CISA KEVcriticalpublic exploit

CVE-2024-38475

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

Q: Is it in CISA KEV?

Yes. The supplied enrichment data lists CVE-2024-38475 in CISA KEV with 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.. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

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 Jul 1, 2024Updated Jun 17, 2026Sources: NVD, Apache Software Foundation (CNA), CISA, FIRST EPSS, GitHub, Red Hat (VEX), SOCRadar CTI

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Confirmed

CISA KEV, listed May 1, 2025

EPSS

100%

top of FIRST's scoreset

Affects

Apache

Apache HTTP Server

CVSS base

9.1

critical

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

Active

none · proof-of-concept · active

Automatable

Yes

can an attacker script all four kill-chain steps

Technical impact

Total

partial · total control of the vulnerable component

Remediation

The vendor's own words where we have them.

Upgrade Apache HTTP Server to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.

CISA 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.

Federal deadline May 22, 2025 — passed 469 days ago

Red Hat VEX · CVE-2024-38475

fixed749affected0not affected18

vendor_fix: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258

vendor_fix: Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.…

First 24 hours

Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.

Identify exposed assets running affected vendor/product/version combinations.
Treat as emergency remediation because CISA KEV status is present.
Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.

Affected scope

Vendor, product and version as the advisories word them.

Vendor	Product	Versions	Status
Apache	Apache HTTP Server	2.4.0 to <= 2.4.59	Vulnerable

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Availability

None

Confidentiality

High

Integrity

High

Scope

Unchanged

Attack Complexity

Low

Attack Vector

Network

Privileges Req

None

User Interaction

None

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
9.1	CVSS 3.1	critical	3.9	5.2	NVD, CNA, Red Hat (VEX)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

What this weakness leads to

MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.

MITRE

CWE-116 · Improper Encoding or Escaping of Output

Modify Application Data
Execute Unauthorized Code or Commands
Bypass Protection Mechanism

Mitigation: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using the ESAPI Encoding control [REF-45] or a similar tool, library, or framework. These will help the programmer encode outputs in a manner less prone to error. Alternately, use built-in functions, but consider using wrappers in case those functions are discovered to have a vulnerability.

Weakness & attack patterns

CWE-116

Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.

CAPEC-81 · Web Logs TamperingCAPEC-104 · Cross Zone ScriptingCAPEC-73 · User-Controlled FilenameCAPEC-85 · AJAX Fingerprinting

CISA KEV details

CISA lists a CVE here once it has evidence of exploitation against real targets.

CISAThat month →

Listed

May 1, 2025

Federal deadline

May 22, 2025

passed 469 days ago

Ransomware use

Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a date to argue against.

Public exploit

Capability, not use: code existing is a different claim from anyone running it.

Repositories

2 of the 5 sampled are weaponized

Exploit entries

Exploit-DB and CTI exploit indexes

Malware

Families a CTI source ties to this CVE. One named, with the total it tracks.

Families tracked

Named

OVERSTEP

Social mentions

Posts naming this CVE. Attention, not evidence of exploitation — it spikes on disclosure and decays whether or not anything is exploited.

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

Search application, proxy, and WAF logs for requests touching /directly.
Prioritize edge telemetry for network-reachable Apache HTTP Server.
Monitor for scanner or exploit-pattern traffic after 31 public PoC repositories were reported.

web/proxy/WAF logsapplication logsnetwork IDS/IPS

Groups associated with this CVE

Groups reported in connection with this vulnerability. A reported association, not a confirmed observation of that group using it — and not scoped to any sector or campaign.

Mana TeamLucky CatRed OctoberHacking TeamUNC6148

ip187.141.210.9257
Maltrail Malware Feeds · Dec 17, 2024
ip187.111.28.13121
blocklist.net.ua-Firehol · Oct 21, 2022
ip187.111.19.18262
AbuseIPDB Hourly Update · Aug 29, 2026
ip187.110.238.5030
Zonefiles · Nov 17, 2023
ip187.16.96.25039
Zonefiles · Dec 15, 2023

5 more indicators on this CVEShowing 5 of 10 · Hashes, addresses and domains from a live threat exchangeUnlock free

Timeline

What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.

2026
Added · CVSS 3.1 9.1 (AV:N)
Jun 17, 2026 · NVD
2025
Added to CISA KEV catalog
May 1, 2025 · CISA
2024
Initial · CVE published
Jul 1, 2024 · NVD
reported
Apr 1, 2024 · Apache Software Foundation

Source activity

Readings a source repeats on a schedule, counted rather than listed.

20×SVRS was changedMay 15, 2025 – Aug 4, 2025 · SOCRadar CTI
8×TweetsMay 15, 2025 – Apr 11, 2026 · SOCRadar CTI
1×2 times mentioned on 1 Telegram channelsApr 25, 2026 · SOCRadar CTI

References

17 on the record

httpd.apache.org/security/vulnerabilities_24.html
Vendor Advisory, NIST
security.netapp.com/advisory/ntap-20240712-0001/
Third Party Advisory, NIST
www.openwall.com/lists/oss-security/2024/07/01/8
Third Party Advisory, NIST
github.com/apache/httpd/commit/9a6157d1e2f7ab15963020381054b48782bc18cf
Patch, NIST
psirt.global.sonicwall.com/vuln-detail/SNWLID-2024-0018
Third Party Advisory, NIST
www.blackhat.com/us-24/briefings/schedule/index.html#confusion-attacks-exploiting-hidden-semantic-ambiguity-in-apache-http-server-pre-recorded-40227
Third Party Advisory, NIST
www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-38475
Third Party Advisory, US Government Resource
access.redhat.com/errata/RHSA-2024:4938
Vendor Advisory

Coverage

3 stories from the feeds we poll

Elsewhere on this site

Apacheevery CVE for this vendor
May 2025what else CISA listed
Unclassifiedsame class
CWE-116other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

Only the 5 indicator(s) reported for this CVE are available; no packet-level or host-forensic artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record1

What should defenders know first?

CVE-2024-38475 is Apache HTTP Server weakness in mod_rewrite when first segment of substitution matches filesystem path., a critical vulnerability affecting Apache HTTP Server from Apache Software Foundation. The current evidence lists it in CISA KEV, and the exploit status is: Yes: CISA KEV signal present. Public exploit evidence is: 31 public PoC repositories reported; 2 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 9.1 describes technical severity, while EPSS 100% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.