VulnerabilityPublished 5 Dec 2023Updated 4 Nov 2025

CVE-2023-41835: Apache Struts · Incomplete Cleanup

Affects Apache StrutsSource CVE Database V5

Not known to be exploited · CVSS 7.5 High.

Data as of 26 Oct 2026, 11:42 UTC

CVSS 3.1 base score

7.5High

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

EPSS: 7.3% chance of exploitation in 30 days – higher than 94% 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:N/I:N/A:H

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

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: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 5 Dec 2023
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 26 Oct 2026.

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 or the CVSS exploit maturity 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
Mavenorg.apache.struts/struts2-core`pkg:maven/org.apache.struts/struts2-core`Other threats	Affected =2.0.0 =6.1.2.1	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

European organizations should immediately upgrade Apache Struts to versions 2.5.32, 6.1.2.2, 6.3.0.1, or later to remediate this vulnerability. In addition to patching, organizations should implement monitoring of the struts.multipart.saveDir directory to detect abnormal file accumulation indicative of exploitation attempts. Automated cleanup scripts or scheduled tasks can be employed as a temporary mitigation to remove orphaned files and prevent disk exhaustion. Web application firewalls (WAFs) can be configured to limit the size of multipart requests or block requests with fields exceeding expected length thresholds. Organizations should also review and tighten maxStringLength configurations to reasonable limits based on application requirements. Regular audits of disk usage and alerting on unusual spikes can help detect early signs of exploitation. Finally, integrating vulnerability scanning and patch management processes will ensure timely detection and remediation of similar issues in the future.

Description

When a Multipart request is performed but some of the fields exceed the maxStringLength limit, the upload files will remain in struts.multipart.saveDir even if the request has been denied. Users are recommended to upgrade to versions Struts 2.5.32 or 6.1.2.2 or Struts 6.3.0.1 or greater, which fixe this issue.

Impact

For European organizations, the primary impact of CVE-2023-41835 is on the availability of web applications built on vulnerable Apache Struts versions. Residual files from denied multipart requests can accumulate, leading to disk space exhaustion and service outages. This can disrupt business operations, especially for critical services relying on Struts-based applications, such as government portals, financial services, and e-commerce platforms. The vulnerability does not expose sensitive data or allow code execution but can degrade service reliability and availability, potentially causing reputational damage and financial losses. Organizations with high traffic or frequent file uploads are at greater risk. Additionally, cleanup and recovery efforts post-exploitation can increase operational costs. The lack of authentication requirements and remote exploitability means attackers can easily attempt to exploit this vulnerability at scale, increasing the risk of denial of service attacks targeting European enterprises.

CWE-459Incomplete Cleanup (opens in a new tab)
Base weakness
The product does not properly "clean up" and remove temporary or supporting resources after they have been used.
Architecture and Design · Implementation
Temporary files and other supporting resources should be deleted/released immediately after they are no longer needed.
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 4 Nov 2025, 20:08 UTC

WeaknessesCWE-459

Technical details

References

Community reviews

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