CWE-367
Time-of-check Time-of-use (TOCTOU) Race Condition
The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
CVE-2026-7724 (GCVE-0-2026-7724)
Vulnerability from cvelistv5 – Published: 2026-05-04 02:45 – Updated: 2026-05-05 00:54 X_Open Source
VLAI
Title
PrefectHQ prefect Webhook/Notification validate_restricted_url toctou
Summary
A vulnerability has been found in PrefectHQ prefect up to 3.6.28.dev1. Affected by this vulnerability is the function validate_restricted_url of the component Webhook/Notification. The manipulation leads to time-of-check time-of-use. It is possible to initiate the attack remotely. The attack is considered to have high complexity. The exploitation appears to be difficult. The exploit has been disclosed to the public and may be used. Upgrading to version 3.6.28.dev2 addresses this issue. The identifier of the patch is 7c70ac54a5e101431d83b9f2681ec88d5e0021ed. Upgrading the affected component is advised. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
Severity
Assigner
References
9 references
| URL | Tags |
|---|---|
| https://vuldb.com/vuln/360900 | vdb-entrytechnical-description |
| https://vuldb.com/vuln/360900/cti | signaturepermissions-required |
| https://vuldb.com/submit/807303 | third-party-advisory |
| https://linear.app/prefect/issue/OSS-7874/fix-dns… | issue-tracking |
| https://github.com/PrefectHQ/prefect/pull/21591 | issue-trackingpatch |
| https://gist.github.com/nedlir/fa99777e8989414585… | exploit |
| https://github.com/PrefectHQ/prefect/commit/7c70a… | patch |
| https://github.com/PrefectHQ/prefect/releases/tag… | patch |
| https://github.com/PrefectHQ/prefect/ | product |
Impacted products
Credits
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CVE-2026-7791 (GCVE-0-2026-7791)
Vulnerability from cvelistv5 – Published: 2026-05-04 22:07 – Updated: 2026-05-06 03:56
VLAI
Summary
Improper privilege management in the log rotation mechanism of the Skylight Workspace Config Service in Amazon WorkSpaces for Windows before 2.6.2034.0 allows a local non-admin authenticated user to place arbitrary files into arbitrary locations bypassing file system permission protections, leading to local privilege escalation to SYSTEM.
Severity
CWE
- CWE-367 - Time-of-Check Time-of-Use (TOCTOU) Race Condition
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://aws.amazon.com/security/security-bulletin… | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Amazon | Workspaces |
Unaffected:
2.6.2034.0
|
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CVE-2026-7837 (GCVE-0-2026-7837)
Vulnerability from cvelistv5 – Published: 2026-05-21 08:14 – Updated: 2026-05-21 12:50
VLAI
Title
TOCTOU with root privilege in ad_flush
Summary
A time-of-check time-of-use (TOCTOU) condition in the ad_flush function in Netatalk 3.0.0 through 4.4.2 involves root-privileged file operations, which may allow a remote attacker to cause limited data modification under specific race conditions.
Severity
CWE
- CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://netatalk.io/security/CVE-2026-7837 | vendor-advisory |
Impacted products
Date Public
2026-05-13 00:00
Credits
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CVE-2026-7846 (GCVE-0-2026-7846)
Vulnerability from cvelistv5 – Published: 2026-05-05 16:00 – Updated: 2026-05-05 16:11
VLAI
Title
chatchat-space Langchain-Chatchat OpenAI-Compatible File Upload API openai_routes.py files toctou
Summary
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Severity
Assigner
References
6 references
| URL | Tags |
|---|---|
| https://vuldb.com/vuln/361125 | vdb-entrytechnical-description |
| https://vuldb.com/vuln/361125/cti | signaturepermissions-required |
| https://vuldb.com/submit/807795 | third-party-advisory |
| https://github.com/chatchat-space/Langchain-Chatc… | issue-tracking |
| https://github.com/3em0/cve_repo/blob/main/Langch… | exploit |
| https://github.com/chatchat-space/Langchain-Chatchat/ | product |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| chatchat-space | Langchain-Chatchat |
Affected:
0.3.1.0
Affected: 0.3.1.1 Affected: 0.3.1.2 Affected: 0.3.1.3 |
Credits
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CVE-2026-9796 (GCVE-0-2026-9796)
Vulnerability from cvelistv5 – Published: 2026-05-28 04:27 – Updated: 2026-05-28 12:16
VLAI
Title
Keycloak: keycloak: privilege escalation via time-of-check to time-of-use (toctou) vulnerability
Summary
A flaw was found in Keycloak. An authenticated administrator with the `manage-clients` role can exploit a Time-of-check to time-of-use (TOCTOU) vulnerability in the name-based admin role checks. This allows the attacker to escalate their privileges to `realm-admin` for all users within the realm, granting them extensive control over the system. The composite role relationship persists even after the attacker's own permissions are revoked and across system reboots.
Severity
6.5 (Medium)
CWE
- CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-9796 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2482464 | issue-trackingx_refsource_REDHAT |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Red Hat | Red Hat Build of Keycloak |
cpe:/a:redhat:build_keycloak: |
Date Public
2026-05-28 03:32
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Mitigation
Phase: Implementation
Description:
- The most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.
Mitigation
Phase: Implementation
Description:
- When the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.
Mitigation
Phase: Architecture and Design
Description:
- Limit the interleaving of operations on files from multiple processes.
Mitigation
Phases: Implementation, Architecture and Design
Description:
- If you cannot perform operations atomically and you must share access to the resource between multiple processes or threads, then try to limit the amount of time (CPU cycles) between the check and use of the resource. This will not fix the problem, but it could make it more difficult for an attack to succeed.
Mitigation
Phase: Implementation
Description:
- Recheck the resource after the use call to verify that the action was taken appropriately.
Mitigation
Phase: Architecture and Design
Description:
- Ensure that some environmental locking mechanism can be used to protect resources effectively.
Mitigation
Phase: Implementation
Description:
- Ensure that locking occurs before the check, as opposed to afterwards, such that the resource, as checked, is the same as it is when in use.
CAPEC-27: Leveraging Race Conditions via Symbolic Links
This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to them. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file they will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary file.
CAPEC-29: Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions
This attack targets a race condition occurring between the time of check (state) for a resource and the time of use of a resource. A typical example is file access. The adversary can leverage a file access race condition by "running the race", meaning that they would modify the resource between the first time the target program accesses the file and the time the target program uses the file. During that period of time, the adversary could replace or modify the file, causing the application to behave unexpectedly.