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Full vulnerability report · 2024
CVE-2024-38475High confidence

Apache HTTP Server Improper Escaping of Output Vulnerability

Apache · HTTP Server

9.1CriticalCVSS 3.1
Recommended action
Patch now

CISA confirms exploitation in the wild and lists 2025-05-22 as the remediation due date.

Patch available
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

1 package state
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archiveapache2Vendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree.2.4.58-1ubuntu8.2Canonical record ↗Source updated 10 Sept 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2024-37356

CISA KEV mirrored by ENISA

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.

EUVD state
Present in the current official mapping
Known exploitation
Recorded by ENISA since 1 May 2025. Evidence sources: cisa_kev.
ENISA score
9.1 · CVSS 3.1
Advisory evidence
25 linked advisory records
Explicit mitigation evidence

Only statements that explicitly mention a fix, patch, update, workaround or mitigation are shown here.

  • csaf_redhat · RHSA-2024:4820Red Hat Security Advisory: httpd:2.4 security update
  • csaf_redhat · RHSA-2024:4938Red Hat Security Advisory: httpd security update
  • csaf_suse · SUSE-SU-2024:2591-1Security update for apache2
  • csaf_ncscnl · NCSC-2025-0027Kwetsbaarheden verholpen in Oracle Fusion Middleware
  • csaf_redhat · RHSA-2024:4726Red Hat Security Advisory: httpd security update
  • csaf_suse · SUSE-SU-2024:2597-1Security update for apache2
  • csaf_redhat · RHSA-2024:5240Red Hat Security Advisory: Red Hat JBoss Core Services Apache HTTP Server 2.4.57 SP5 security update
  • csaf_ncscnl · NCSC-2024-0275Kwetsbaarheden verholpen in Apache HHTP-server
  • csaf_redhat · RHSA-2024:4720Red Hat Security Advisory: httpd:2.4 security update
  • csaf_redhat · RHSA-2024:5239Red Hat Security Advisory: Red Hat JBoss Core Services Apache HTTP Server 2.4.57 SP5 security update
  • csaf_suse · SUSE-SU-2024:2436-1Security update for apache2
  • csaf_redhat · RHSA-2024:4827Red Hat Security Advisory: httpd:2.4 security update
  • csaf_redhat · RHSA-2024:4862Red Hat Security Advisory: httpd security update
  • csaf_ncscnl · NCSC-2024-0464Kwetsbaarheden verholpen in SonicWall SMA100 SSLVPN
  • csaf_redhat · RHSA-2024:4719Red Hat Security Advisory: httpd:2.4 security update
  • csaf_redhat · RHSA-2024:4830Red Hat Security Advisory: httpd:2.4 security update
  • csaf_ncscnl · NCSC-2024-0411Kwetsbaarheden verholpen in Oracle Database producten
  • csaf_redhat · RHSA-2024:4943Red Hat Security Advisory: httpd security update
  • csaf_ncscnl · NCSC-2025-0021Kwetsbaarheden verholpen in Oracle Communications
  • csaf_redhat · RHSA-2024:4863Red Hat Security Advisory: httpd security update
  • csaf_suse · SUSE-SU-2024:2624-1Security update for apache2
Recommended actionPatch now

CISA confirms exploitation in the wild and lists 2025-05-22 as the remediation due date.

Patch available
01

What, why and how

Apache HTTP Server contains an improper escaping of output vulnerability in mod_rewrite that 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.

What

Apache HTTP Server contains an improper escaping of output vulnerability in mod_rewrite that 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.

Why

The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Apache HTTP Server contains an improper escaping of output vulnerability in mod_rewrite that 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.

Why

The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Confirmed in the wild

CISA added this CVE to its Known Exploited Vulnerabilities catalogue on 2025-05-01.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Improper Encoding or Escaping of Output → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-116 ↗

CWE-116: Improper Encoding or Escaping of Output. The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-116CISA KEV
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2024-37356Known-exploited evidence recorded

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.

Official EUVD record
BSI · German · WID-SEC-W-2025-0148Oracle Communications: Mehrere Schwachstellen

Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Oracle Communications ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.

Official advisory
BSI · German · WID-SEC-W-2025-0143Oracle Fusion Middleware: Mehrere Schwachstellen

Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Oracle Fusion Middleware ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.

Official advisory
BSI · German · WID-SEC-W-2024-1504Apache HTTP Server: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Apache HTTP Server ausnutzen, um beliebigen Code auszuführen, einen Denial-of-Service-Zustand herbeizuführen, Sicherheitsmaßnahmen zu umgehen oder vertrauliche Informationen offenzulegen.

Official advisory
CERT-FR · French · CERTFR-2024-AVI-1042Multiples vulnérabilités dans Sonicwall Secure Mobile Access

De multiples vulnérabilités ont été découvertes dans Sonicwall Série Secure Mobile Access 100. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, une atteinte à la confidentialité des données et un contournement de la politique de sécurité.

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0750Multiples vulnérabilités dans les produits IBM

d?id=CVE-2024-35153 Référence CVE CVE-2024-35154 https://www.cve.org/CVERecord?id=CVE-2024-35154 Référence CVE CVE-2024-35195 https://www.cve.org/CVERecord?id=CVE-2024-35195 Référence CVE CVE-2024-37532 https://www.cve.org/CVERecord?id=CVE-2024-37532 Référence CVE CVE-2024-37890 https://www.cve.org/CVERecord?id=CVE-2024-37890 Référence CVE CVE-2024-37891 https://www.cve.org/CVERecord?id=CVE-2024-37891 Référence CVE CVE-2024-38472 https://www.cve.org/CVERecord?id=CVE-2024-38472 Référence CVE CVE-2024-38473 https://www.cve.org/CVERecord?id=CVE-2024-38473 Référence CVE CVE-2024-38474 https://www.cve.org/CVERecord?id=CVE-2024-38474 Référence CVE CVE-2024-38475 https://www.cve.org/CVERecord?id=CVE-2024-38475 Référence CVE CVE-2024-38476 https://www.cve.org/CVERecord?id=CVE-2024-38476 Référence CVE CVE-2024-38477 https://www.cve.org/CVERecord?id=CVE-2024-38477 Référence CVE CVE-2024-39338 https://www.cve.org/CVERecord?id=CVE-2024-39338 Référence CVE CVE-2024-39573 https://www.cve.org/CVERecord?id=CVE-2024-39573 Référence CVE CVE-2024-39689 https://www.cve.org/CVERecord?id=CVE-2024-39689 Référence CVE CVE-2024-39705 https://www.cve.org/CVERecord?id=CVE-2024-39705 Référence CVE CVE-2024-39884 https://www.cve.org/CVERecord?id=CVE-2024-39884 Référence CVE CVE-2024-4068 https://www.cve.org/CVERecord?id=C

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0676Multiples vulnérabilités dans Tenable Security Center

De multiples vulnérabilités ont été découvertes dans Tenable Security Center. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et une atteinte à la confidentialité des données.

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0533Multiples vulnérabilités dans Apache HTTP Server

De multiples vulnérabilités ont été découvertes dans Apache HTTP Server. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et une atteinte à la confidentialité des données.

Official advisory
NCSC-NL · Dutch · NCSC-2025-0021Kwetsbaarheden verholpen in Oracle Communications

De kwetsbaarheden stellen ongeauthenticeerde kwaadwillenden in staat om Denial of Service (DoS) aanvallen uit te voeren of om ongeautoriseerde toegang tot gevoelige gegevens te verkrijgen. Specifieke versies, zoals 24.2.0 en 24.3.0 van de Cloud Native Core Network Function, zijn bijzonder kwetsbaar. Kwaadwillenden kunnen deze kwetsbaarheden misbruiken door speciaal geprepareerde HTTP-verzoeken te sturen naar het kwetsbare systeem.

Official advisory
NCSC-NL · Dutch · NCSC-2024-0464Kwetsbaarheden verholpen in SonicWall SMA100 SSLVPN

De kwetsbaarheden in de SonicWall SMA100 SSLVPN omvatten een heap-gebaseerde buffer overflow, een stack-gebaseerde buffer overflow, en een probleem met de certificaatvereiste tijdens authenticatie. Deze kwetsbaarheden kunnen door remote geauthenticeerde aanvallers worden misbruikt om willekeurige code uit te voeren op de getroffen systemen, wat kan leiden tot ongeautoriseerde toegang en controle over gevoelige gegevens. Daarnaast is er een zwakte in de pseudo-willekeurige getallengenerator (PRNG) die de integriteit van SSLVPN-verbindingen in gevaar kan brengen.

Official advisory
NCSC-NL · Dutch · NCSC-2025-0027Kwetsbaarheden verholpen in Oracle Fusion Middleware

De kwetsbaarheden bevinden zich in verschillende Oracle producten, waaronder Oracle WebLogic Server versies 12.2.1.4.0 en 14.1.1.0.0, die het mogelijk maken voor ongeauthenticeerde kwaadwillenden om toegang te krijgen tot kritieke gegevens. Dit kan leiden tot ernstige gevolgen voor de vertrouwelijkheid, integriteit en beschikbaarheid van de systemen. De kwetsbaarheid in Oracle HTTP Server versie 12.2.1.4.0 stelt kwaadwillenden in staat om ongeautoriseerde toegang te verkrijgen, met een CVSS-score van 5.3, terwijl de kwetsbaarheid in WebLogic Server een CVSS-score van 9.8 heeft, wat wijst op een kritieke impact. Kwaadwillenden kunnen ook gebruik maken van kwetsbaarheden in Oracle Fusion Middleware en andere producten om Denial-of-Service (DoS) aanvallen uit te voeren.

Official advisory
NCSC-NL · Dutch · NCSC-2024-0411Kwetsbaarheden verholpen in Oracle Database producten

Een kwaadwillende kan de kwetsbaarheden misbruiken om aanvallen uit te voeren die kunnen leiden tot de volgende categorieën schade: - Denial-of-Service (DoS) - Manipuleren van data - Toegang tot gevoelige gegevens

Official advisory
NCSC-NL · Dutch · NCSC-2024-0275Kwetsbaarheden verholpen in Apache HHTP-server

Een kwaadwillende kan de kwetsbaarheden misbruiken om een Denial-of-Service te veroorzaken, middels een Server-Side-Request-Forgery (SSRF) verkeer te manipuleren, of om code uit te voeren binnen de webserver, waarvoor de kwaadwillende aanvankelijk niet is geautoriseerd.

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
2.4.0 ≤ 2.4.59
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 1 Jul 2024 · Last source change 3 Nov 2025, 21:55 UTC · CWE-116 · Improper Encoding or Escaping of Output

CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2024-37356
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Added to CISA KEV
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2024-37356↗CISA KEV record↗CVE authority or vendor reference↗Patch or update reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2024-38475 · cve.blacktree.nl