CVE-2025-55668VulnerabilityPublished 13 Aug 2025Updated 4 Nov 2025

CVE-2025-55668: Apache Tomcat · Session Fixation

Affects Apache TomcatSource CVE Database V5

Not known to be exploited · CVSS 6.5 Medium · fixed in 11.0.8 : update Apache Tomcat when convenient.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

6.5Medium

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

EPSS: 0.8% chance of exploitation in 30 days – higher than 58% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 11.0.8

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
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: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
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 13 Aug 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 2026-10-25.

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
Apache Software Foundation Apache Tomcat	Affected =11.0.0-M1 =10.1.0-M1	Fixed in–

AI-suggested

1. Upgrade Apache Tomcat to the fixed versions: 9.0.106, 10.1.42, or 11.0.8 as soon as possible to ensure the vulnerability is patched. 2. Review and harden session management policies, ensuring session IDs are regenerated upon authentication and that session fixation protections are enabled. 3. Implement web application firewalls (WAFs) to detect and block suspicious session fixation attempts or abnormal session behaviors. 4. Educate users about phishing and social engineering risks that could facilitate session fixation exploitation. 5. Conduct regular security assessments and penetration testing focusing on session management vulnerabilities. 6. Monitor logs for unusual session activity or repeated session ID reuse patterns. 7. For legacy or EOL Tomcat versions that cannot be immediately upgraded, consider isolating affected services behind additional security layers or reverse proxies that can enforce session security controls.

Description

Session Fixation vulnerability in Apache Tomcat via rewrite valve. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.7, from 10.1.0-M1 through 10.1.41, from 9.0.0.M1 through 9.0.105. Older, EOL versions may also be affected. Users are recommended to upgrade to version 11.0.8, 10.1.42 or 9.0.106, which fix the issue.

Impact

For European organizations, this vulnerability poses a risk of unauthorized access to sensitive web applications hosted on Apache Tomcat servers. Attackers exploiting this flaw can hijack user sessions, potentially gaining access to confidential data, internal systems, or administrative interfaces without needing credentials. This can lead to data breaches, compliance violations (e.g., GDPR), and reputational damage. Sectors such as finance, healthcare, government, and critical infrastructure are particularly vulnerable due to their reliance on secure web services. The medium severity score indicates a moderate but tangible risk, especially in environments where session management is critical. Since exploitation requires user interaction, phishing or social engineering could be used to lure victims into using attacker-controlled session IDs. The absence of known exploits currently reduces immediate risk but does not eliminate the threat, especially as attackers often develop exploits rapidly after disclosure.

CWE-384Session Fixation (opens in a new tab)
Compound weaknessOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions.
Architecture and Design
Invalidate any existing session identifiers prior to authorizing a new user session.
Architecture and Design
For platforms such as ASP that do not generate new values for sessionid cookies, utilize a secondary cookie. In this approach, set a secondary cookie on the user's browser to a random value and set a session variable to the same value.
Operation · Firewall
Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.
OWASP Cheat Sheets
Session Management (opens in a new tab)
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V3.2.1 (opens in a new tab)
Attack patterns
Session Credential Falsification through Forging (opens in a new tab)
Accessing/Intercepting/Modifying HTTP Cookies (opens in a new tab)
Manipulating Opaque Client-based Data Tokens (opens in a new tab)
Session Credential Falsification through Prediction (opens in a new tab)
Reusing Session IDs (aka Session Replay) (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 5 Nov 2025, 15:50 UTC

WeaknessesCWE-384

Technical details

References

Community reviews

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