CVE-2024-47252VulnerabilityPublished 10 Jul 2025Updated 4 Nov 2025

CVE-2024-47252: Apache HTTP Server · Improper Neutralization of Escape, Meta, or Control Sequences

Affects Apache HTTP ServerSource CVE Database V5

Not known to be exploited · CVSS 7.5 High.

Data as of 26 Oct 2026, 07:57 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.7% chance of exploitation in 30 days – higher than 56% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 10 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Apacheapache/httpd`pkg:rpm/apache/httpd`Other threats	Affected <=2.4.63	Fixed in–

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AI-suggested

European organizations should immediately audit their Apache HTTP Server configurations to identify usage of CustomLog directives with "%{varname}x" or "%{varname}c" format specifiers that log mod_ssl variables such as SSL_TLS_SNI. Until an official patch is available, administrators should consider disabling logging of these variables or implementing manual sanitization of input data before logging. Employing log management solutions that can detect and filter suspicious escape sequences in logs can help mitigate exploitation impact. Monitoring logs for anomalous entries containing escape characters or control sequences is recommended. Additionally, organizations should plan to apply vendor patches promptly once released. Network-level controls such as restricting access to the Apache HTTP Server to trusted clients and employing TLS client authentication can reduce exposure. Finally, integrating log integrity verification mechanisms and alerting on unexpected log modifications can enhance detection capabilities.

Description

Insufficient escaping of user-supplied data in mod_ssl in Apache HTTP Server 2.4.63 and earlier allows an untrusted SSL/TLS client to insert escape characters into log files in some configurations. In a logging configuration where CustomLog is used with "%{varname}x" or "%{varname}c" to log variables provided by mod_ssl such as SSL_TLS_SNI, no escaping is performed by either mod_log_config or mod_ssl and unsanitized data provided by the client may appear in log files.

Impact

For European organizations, this vulnerability poses a significant risk to the integrity and reliability of security logs, which are critical for incident detection, response, and compliance with regulations such as GDPR and NIS Directive. Log injection can lead to falsified or misleading log entries, complicating forensic investigations and potentially allowing attackers to cover their tracks. This undermines trust in security monitoring systems and may delay detection of breaches. Organizations relying heavily on Apache HTTP Server 2.4.x with mod_ssl and custom logging configurations that include SSL/TLS variables are particularly at risk. Critical infrastructure providers, financial institutions, and public sector entities in Europe that depend on accurate logging for regulatory compliance and security monitoring could face increased operational risk. Although availability and integrity of the server itself are not directly impacted, the confidentiality and trustworthiness of log data are compromised, which can have cascading effects on security posture and incident management.

CWE-150Improper Neutralization of Escape, Meta, or Control Sequences (opens in a new tab)
Variant weakness
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as escape, meta, or control character sequences when they are sent to a downstream component.
Developers should anticipate that escape, meta and control characters/sequences will be injected/removed/manipulated in the input vectors of their product. Use an appropriate combination of denylists and allowlists to ensure only valid, expected and appropriate input is processed by the system.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
Implementation · Output Encoding
While it is risky to use dynamically-generated query strings, code, or commands that mix control and data together, sometimes it may be unavoidable. Properly quote arguments and escape any special characters within those arguments.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
Server Side Request Forgery Prevention (opens in a new tab)
Unvalidated Redirects and Forwards (opens in a new tab)
Cross Site Scripting Prevention (opens in a new tab)
OWASP ASVS 4.0.3
V1.5.1 (opens in a new tab)
V5.2.2 (opens in a new tab)
Attack patterns
Email Injection (opens in a new tab)
Using Meta-characters in E-mail Headers to Inject Malicious Payloads (opens in a new tab)
Web Server Logs Tampering (opens in a new tab)
Log Injection-Tampering-Forging (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 10 Nov 2025, 20:23 UTC

WeaknessesCWE-150

Technical details

References

Community reviews

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