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CWE-203

826 CVEs • Abstraction: Base

Observable Discrepancy

The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not.

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CVEs (826)

CVE
VENDORS
PRODUCTS
UPDATED
PUBLISHED
CVSS
1Kanboard
1Kanboard
Jun 17, 2026
Jun 25, 2025
N/A· v4
5.3 MEDIUM· v3
N/A· v2
Kanboard is project management software that focuses on the Kanban methodology. Prior to version 1.2.46, Kanboard is vulnerable to username enumeration and IP spoofing-based brute-force protection bypass. By analyzing lo...Show more
Kanboard is project management software that focuses on the Kanban methodology. Prior to version 1.2.46, Kanboard is vulnerable to username enumeration and IP spoofing-based brute-force protection bypass. By analyzing login behavior and abusing trusted HTTP headers, an attacker can determine valid usernames and circumvent rate-limiting or blocking mechanisms. Any organization running a publicly accessible Kanboard instance is affected, especially if relying on IP-based protections like Fail2Ban or CAPTCHA for login rate-limiting. Attackers with access to the login page can exploit this flaw to enumerate valid usernames and bypass IP-based blocking mechanisms, putting all user accounts at higher risk of brute-force or credential stuffing attacks. Version 1.2.46 contains a patch for the issue.Show less
1Vllm
1Vllm
Jun 17, 2026
May 29, 2025
N/A· v4
2.6 LOW· v3
N/A· v2
vLLM is an inference and serving engine for large language models (LLMs). Prior to version 0.9.0, when a new prompt is processed, if the PageAttention mechanism finds a matching prefix chunk, the prefill process speeds u...Show more
vLLM is an inference and serving engine for large language models (LLMs). Prior to version 0.9.0, when a new prompt is processed, if the PageAttention mechanism finds a matching prefix chunk, the prefill process speeds up, which is reflected in the TTFT (Time to First Token). These timing differences caused by matching chunks are significant enough to be recognized and exploited. This issue has been patched in version 0.9.0.Show less
-
-
Jun 17, 2026
May 28, 2025
N/A· v4
5.3 MEDIUM· v3
N/A· v2
SummaryThis advisory addresses a security vulnerability in Mautic related to the "Forget your password" functionality. This vulnerability could be exploited by unauthenticated users to enumerate valid usernames. User En...Show more
SummaryThis advisory addresses a security vulnerability in Mautic related to the "Forget your password" functionality. This vulnerability could be exploited by unauthenticated users to enumerate valid usernames. User Enumeration via Timing Attack: A user enumeration vulnerability exists in the "Forget your password" functionality. Differences in response times for existing and non-existing users, combined with a lack of request limiting, allow an attacker to determine the existence of usernames through a timing-based attack. MitigationPlease update to a version that addresses this timing vulnerability, where password reset responses are normalized to respond at the same time regardless of user existence.Show less
-
-
Jun 17, 2026
May 26, 2025
2.0 LOW· v4
3.3 LOW· v3
N/A· v2
A minor information leak when running Screen with setuid-root privileges allows unprivileged users to deduce information about a path that would otherwise not be available. Affected are older Screen versions, as well a...Show more
A minor information leak when running Screen with setuid-root privileges allows unprivileged users to deduce information about a path that would otherwise not be available. Affected are older Screen versions, as well as version 5.0.0.Show less
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-
Jun 17, 2026
May 22, 2025
N/A· v4
4.3 MEDIUM· v3
N/A· v2
CWE-203: Observable Discrepancy
1Tridium
2Niagara
Niagara Enterprise Security
Jun 17, 2026
May 22, 2025
N/A· v4
5.3 MEDIUM· v3
N/A· v2
Observable Response Discrepancy vulnerability in Tridium Niagara Framework on Windows, Linux, QNX, Tridium Niagara Enterprise Security on Windows, Linux, QNX allows Cryptanalysis. This issue affects Niagara Framework: be...Show more
Observable Response Discrepancy vulnerability in Tridium Niagara Framework on Windows, Linux, QNX, Tridium Niagara Enterprise Security on Windows, Linux, QNX allows Cryptanalysis. This issue affects Niagara Framework: before 4.14.2, before 4.15.1, before 4.10.11; Niagara Enterprise Security: before 4.14.2, before 4.15.1, before 4.10.11.Tridium recommends upgrading to Niagara Framework and Enterprise Security versions 4.14.2u2, 4.15.u1, or 4.10u.11.Show less
1Keystonejs
1Keystone
Jun 17, 2026
May 5, 2025
N/A· v4
4.3 MEDIUM· v3
N/A· v2
Keystone is a content management system for Node.js. Prior to version 6.5.0, `{field}.isFilterable` access control can be bypassed in `update` and `delete` mutations by adding additional unique filters. These filters can...Show more
Keystone is a content management system for Node.js. Prior to version 6.5.0, `{field}.isFilterable` access control can be bypassed in `update` and `delete` mutations by adding additional unique filters. These filters can be used as an oracle to probe the existence or value of otherwise unreadable fields. Specifically, when a mutation includes a `where` clause with multiple unique filters (e.g. `id` and `email`), Keystone will attempt to match records even if filtering by the latter fields would normally be rejected by `field.isFilterable` or `list.defaultIsFilterable`. This can allow malicious actors to infer the presence of a particular field value when a filter is successful in returning a result. This affects any project relying on the default or dynamic `isFilterable` behavior (at the list or field level) to prevent external users from using the filtering of fields as a discovery mechanism. While this access control is respected during `findMany` operations, it was not completely enforced during `update` and `delete` mutations when accepting more than one unique `where` values in filters. This has no impact on projects using `isFilterable: false` or `defaultIsFilterable: false` for sensitive fields, or for those who have otherwise omitted filtering by these fields from their GraphQL schema. This issue has been patched in `@keystone-6/core` version 6.5.0. To mitigate this issue in older versions where patching is not a viable pathway, set `isFilterable: false` statically for relevant fields to prevent filtering by them earlier in the access control pipeline (that is, don't use functions); set `{field}.graphql.omit.read: true` for relevant fields, which implicitly removes filtering by these fields from the GraphQL schema; and/or deny `update` and `delete` operations for the relevant lists completely.Show less
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-
Jun 17, 2026
Apr 24, 2025
N/A· v4
5.3 MEDIUM· v3
N/A· v2
Due to improper authentication mechanism an unauthenticated remote attacker can enumerate valid usernames.
1Espocrm
1Espocrm
Jun 17, 2026
Apr 16, 2025
N/A· v4
3.7 LOW· v3
N/A· v2
EspoCRM is an Open Source Customer Relationship Management software. Prior to version 9.0.7, users can be sorted by their password hash. This flaw allows an attacker to make assumptions about the hash values of other use...Show more
EspoCRM is an Open Source Customer Relationship Management software. Prior to version 9.0.7, users can be sorted by their password hash. This flaw allows an attacker to make assumptions about the hash values of other users stored in the password column of the user table, based on the results of the sorted list of users. Although unlikely, if an attacker knows the hash value of their password, they can change the password and repeat the sorting until the other user's password hash is fully revealed. This issue is patched in version 9.0.7.Show less
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-
Jun 17, 2026
Apr 15, 2025
6.3 MEDIUM· v4
N/A· v3
N/A· v2
Helix ALM prior to 2025.1 returns distinct error responses during authentication, allowing an attacker to determine whether a username exists.
1Axis
2Axis Os
Axis Os 2024
Jun 17, 2026
Apr 8, 2025
N/A· v4
5.3 MEDIUM· v3
N/A· v2
During an annual penetration test conducted on behalf of Axis Communications, Truesec discovered a flaw in the VAPIX Device Configuration framework that allowed for unauthenticated username enumeration through the VAPIX...Show more
During an annual penetration test conducted on behalf of Axis Communications, Truesec discovered a flaw in the VAPIX Device Configuration framework that allowed for unauthenticated username enumeration through the VAPIX Device Configuration SSH Management API.Show less
1Zitadel
1Zitadel
Jun 17, 2026
Mar 31, 2025
N/A· v4
5.3 MEDIUM· v3
N/A· v2
Zitadel is open-source identity infrastructure software. ZITADEL administrators can enable a setting called "Ignoring unknown usernames" which helps mitigate attacks that try to guess/enumerate usernames. If enabled, ZIT...Show more
Zitadel is open-source identity infrastructure software. ZITADEL administrators can enable a setting called "Ignoring unknown usernames" which helps mitigate attacks that try to guess/enumerate usernames. If enabled, ZITADEL will show the password prompt even if the user doesn't exist and report "Username or Password invalid". While the setting was correctly respected during the login flow, the user's username was normalized leading to a disclosure of the user's existence. This vulnerability is fixed in 2.71.6, 2.70.8, 2.69.9, 2.68.9, 2.67.13, 2.66.16, 2.65.7, 2.64.6, and 2.63.9.Show less
1Ibm
1Infosphere Information Server
Jun 17, 2026
Mar 29, 2025
N/A· v4
6.5 MEDIUM· v3
N/A· v2
IBM InfoSphere Information Server 11.7 could allow an authenticated to obtain sensitive username information due to an observable response discrepancy.
1Fractal
1String\
Jun 17, 2026
Mar 28, 2025
N/A· v4
7.5 HIGH· v3
N/A· v2
String::Compare::ConstantTime for Perl through 0.321 is vulnerable to timing attacks that allow an attacker to guess the length of a secret string. As stated in the documentation: "If the lengths of the strings are diff...Show more
String::Compare::ConstantTime for Perl through 0.321 is vulnerable to timing attacks that allow an attacker to guess the length of a secret string. As stated in the documentation: "If the lengths of the strings are different, because equals returns false right away the size of the secret string may be leaked (but not its contents)." This is similar to CVE-2020-36829Show less
1Openslides
1Openslides
Jun 17, 2026
Mar 21, 2025
N/A· v4
3.7 LOW· v3
N/A· v2
An issue was discovered in OpenSlides before 4.2.5. During login at the /system/auth/login/ endpoint, the system's response times differ depending on whether a user exists in the system. The timing discrepancy stems from...Show more
An issue was discovered in OpenSlides before 4.2.5. During login at the /system/auth/login/ endpoint, the system's response times differ depending on whether a user exists in the system. The timing discrepancy stems from the omitted hashing of the password (e.g., more than 100 milliseconds).Show less
-
-
Jun 17, 2026
Mar 18, 2025
N/A· v4
7.5 HIGH· v3
N/A· v2
An unauthenticated remote attacker can gain access to sensitive information including authentication information when using CODESYS OPC UA Server with the non-default Basic128Rsa15 security policy.
-
-
Jun 17, 2026
Mar 14, 2025
5.8 MEDIUM· v4
N/A· v3
N/A· v2
Post-Quantum Secure Feldman's Verifiable Secret Sharing provides a Python implementation of Feldman's Verifiable Secret Sharing (VSS) scheme. In versions 0.8.0b2 and prior, the `feldman_vss` library contains timing side-...Show more
Post-Quantum Secure Feldman's Verifiable Secret Sharing provides a Python implementation of Feldman's Verifiable Secret Sharing (VSS) scheme. In versions 0.8.0b2 and prior, the `feldman_vss` library contains timing side-channel vulnerabilities in its matrix operations, specifically within the `_find_secure_pivot` function and potentially other parts of `_secure_matrix_solve`. These vulnerabilities are due to Python's execution model, which does not guarantee constant-time execution. An attacker with the ability to measure the execution time of these functions (e.g., through repeated calls with carefully crafted inputs) could potentially recover secret information used in the Verifiable Secret Sharing (VSS) scheme. The `_find_secure_pivot` function, used during Gaussian elimination in `_secure_matrix_solve`, attempts to find a non-zero pivot element. However, the conditional statement `if matrix[row][col] != 0 and row_random < min_value:` has execution time that depends on the value of `matrix[row][col]`. This timing difference can be exploited by an attacker. The `constant_time_compare` function in this file also does not provide a constant-time guarantee. The Python implementation of matrix operations in the _find_secure_pivot and _secure_matrix_solve functions cannot guarantee constant-time execution, potentially leaking information about secret polynomial coefficients. An attacker with the ability to make precise timing measurements of these operations could potentially extract secret information through statistical analysis of execution times, though practical exploitation would require significant expertise and controlled execution environments. Successful exploitation of these timing side-channels could allow an attacker to recover secret keys or other sensitive information protected by the VSS scheme. This could lead to a complete compromise of the shared secret. As of time of publication, no patched versions of Post-Quantum Secure Feldman's Verifiable Secret Sharing exist, but other mitigations are available. As acknowledged in the library's documentation, these vulnerabilities cannot be adequately addressed in pure Python. In the short term, consider using this library only in environments where timing measurements by attackers are infeasible. In the medium term, implement your own wrappers around critical operations using constant-time libraries in languages like Rust, Go, or C. In the long term, wait for the planned Rust implementation mentioned in the library documentation that will properly address these issues.Show less
1Ibm
1Common Cryptographic Architecture
Jun 17, 2026
Mar 11, 2025
N/A· v4
3.7 LOW· v3
N/A· v2
IBM Common Cryptographic Architecture 7.0.0 through 7.5.51 could allow an attacker to obtain sensitive information due to a timing attack during certain RSA operations.
1Printerlogic
2Vasion Print
Virtual Appliance
Jun 17, 2026
Mar 5, 2025
N/A· v4
9.8 CRITICAL· v3
N/A· v2
Vasion Print (formerly PrinterLogic) before Virtual Appliance Host 22.0.843 Application 20.0.1923 allows Administrative User Email Enumeration OVE-20230524-0011.
1Dpgaspar
1Flask Appbuilder
Jun 17, 2026
Mar 3, 2025
N/A· v4
5.3 MEDIUM· v3
N/A· v2
Flask-AppBuilder is an application development framework. Prior to 4.5.3, Flask-AppBuilder allows unauthenticated users to enumerate existing usernames by timing the response time from the server when brute forcing reque...Show more
Flask-AppBuilder is an application development framework. Prior to 4.5.3, Flask-AppBuilder allows unauthenticated users to enumerate existing usernames by timing the response time from the server when brute forcing requests to login. This vulnerability is fixed in 4.5.3.Show less