CVE-2023-6393VulnerabilityPublished 6 Dec 2023Updated 20 Nov 2025

CVE-2023-6393: Red Hat build of Quarkus 2.13.9.Final · Information Exposure

Affects Red Hat build of Quarkus 2.13.9.FinalSource CVE Database V5

Not known to be exploited · CVSS 5.3 Medium.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

5.3Medium

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

EPSS: 0.6% chance of exploitation in 30 days – higher than 50% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: High
Privileges Required: Low
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: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
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 6 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 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

AI-suggested

To mitigate CVE-2023-6393, organizations should first apply any available patches or updates from Red Hat or the Quarkus project that address the caching context reuse issue. If patches are not immediately available, consider disabling caching for Uni objects annotated with @CacheResult in sensitive contexts or avoid caching POST request responses that may contain user-specific data. Implement strict access controls and monitoring around services using Quarkus caching to detect anomalous access patterns. Review application logic to ensure that cached data does not include sensitive information or that context switching is correctly handled per request. Employ network segmentation and firewall rules to limit exposure of vulnerable services to trusted networks only. Additionally, conduct thorough testing of caching behavior in staging environments to verify that context isolation is maintained. Finally, maintain an incident response plan to quickly address any suspected data exposure incidents related to this vulnerability.

Description

A flaw was found in the Quarkus Cache Runtime. When request processing utilizes a Uni cached using @CacheResult and the cached Uni reuses the initial "completion" context, the processing switches to the cached Uni instead of the request context. This is a problem if the cached Uni context contains sensitive information, and could allow a malicious user to benefit from a POST request returning the response that is meant for another user, gaining access to sensitive data.

Impact

For European organizations, the primary impact of CVE-2023-6393 is the unauthorized disclosure of sensitive information, which can lead to data breaches and non-compliance with data protection regulations such as the GDPR. Exposure of personal data or confidential business information could result in reputational damage, regulatory fines, and loss of customer trust. Organizations relying on Red Hat Quarkus for critical applications, especially those handling personal or financial data, are at risk. The vulnerability could be exploited remotely over the network with low privileges, increasing the attack surface. Although the vulnerability does not affect system integrity or availability, the confidentiality breach alone is significant for sectors like finance, healthcare, and government services prevalent in Europe. The risk is heightened in multi-tenant cloud environments or SaaS platforms where cached responses might be shared across users. Consequently, European entities must assess their use of affected Quarkus versions and implement mitigations promptly to avoid potential data leaks.

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 20 Nov 2025, 18:46 UTC

Technical details

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