Weakness (CWE)
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.
How to prevent it (7 mitigations)
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Implementation
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.
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Implementation
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.
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Architecture and Design
Limit the interleaving of operations on files from multiple processes.
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Implementation, Architecture and Design
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.
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Implementation
Recheck the resource after the use call to verify that the action was taken appropriately.
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Architecture and Design
Ensure that some environmental locking mechanism can be used to protect resources effectively.
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Implementation
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.
Source: MITRE CWE-367
852 results · Feed
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Medium 6.5
pgAdmin 4: Files opened in a storage directory follow a symbolic link, hard link or FIFO planted after the containment check
In server mode pgAdmin 4 validates a path a user gives for a file in their storage directory with check_access_permission() and then opened it by name. Several places opened it with a plain open() or handed the path to a utility that opened it later: the serv…
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Medium 6.5
pgAdmin 4: File Manager and storage-path tools act on a different path from the one checked
In server mode pgAdmin 4 validates a path into the user's storage directory with check_access_permission(), which builds the absolute path with get_abs_path(). Several callers then acted on a path they built differently, so the path checked and the path used …
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Medium 5.9
charmbracelet/soft-serve: Race in `SetPrivate` leaves a private repository readable by unauthenticated users
## Summary Soft Serve cached repository records in memory with no expiry, and trusted the cached record for every access check. `SetPrivate` cleared the cached record before it saved the new visibility, and not afterwards. A request that arrived between the t…
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Medium 6.8
epiphany: TLS certificate warning bypass via race in tlsErrorPage message handler
A race condition in Epiphany allows a malicious website to bypass the TLS/SSL certificate warning page. Epiphany registers the main-world script message handler "tlsErrorPage" so its internal TLS error page can implement "Accept Risk and Proceed". The handler…
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Medium 4.8
Uptime Kuma through 2.5.8 Race Condition Admin Creation via Setup Handler
Uptime Kuma through 2.5.8 contains a race condition in the Socket.IO first-run setup handler that allows unauthenticated attackers to create an additional administrator account. Attackers can send concurrent setup requests during the bcrypt hashing window to …
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High 7.8
Privilege Escalation via Insecure Package Handling in TeamViewer Full Client and Host for macOS
A time-of-check time-of-use (TOCTOU) race condition combined with improper symbolic link handling in the privileged helper of TeamViewer Full Client and Host prior to version 15.83 for macOS allows a local attacker with low privileges to bypass installer pack…
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Medium 4.3
Electrum before 4.7.2 Nostr Wallet Connect Plugin Daily Spending Limit Bypass
Electrum before 4.7.2 contains a spending limit bypass vulnerability in the Nostr Wallet Connect plugin that allows malicious NWC clients to exceed daily_limit_sat by exploiting non-atomic budget checks and millisatoshi truncation. Attackers can send concurre…
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Medium 6.5
A memory integrity issue was addressed with improved handling of copy-on-write pages. This issue is fixed in iOS 26.7.2…
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High 8.8
TOCTOU Race Condition in boneIO
boneIO Black contains a TOCTOU race condition in the create_timedatectl_sudoers_file() function in boneio/webui/routes/timezone_sudoers.py. The function writes sudoers rules to a predictable temporary file, validates them, then installs them with root privile…
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Medium 5.4
OpenReception: race condition in add-to-tunnel and create-new-client allows overlapping appointments for one agent
OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 2.2.2, an attacker overbooks an agent, placing multiple appointments into a single time slot that the system is designed to keep exclu…
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Medium 6.5CVE-2026-105481 Public exploit
A flaw in Node.js HTTP Agent connection reuse can cause a client to accept as valid a response that was sent before the…
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High 7.2
PraisonAI: Jobs webhook SSRF protection bypass via DNS rebinding
PraisonAI is a multi-agent teams system. From version 4.5.126 to before version 4.6.59, PraisonAI's Async Jobs API validates webhook_url when a job request is parsed and again when the internal Job object is constructed. That validation blocks direct loopback…
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Medium 6.5
Race condition in DevTools in Google Chrome prior to 156.0.8078.47 allowed a remote attacker leveraging social engineer…
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High 8.8
Race condition in WebProtect in Google Chrome prior to 156.0.8078.47 allowed a remote attacker who had compromised the …
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High 8.8
Race condition in Transactions Platform in Google Chrome prior to 156.0.8078.47 allowed a remote attacker who had compr…
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High 8.8
Race condition in Core in Google Chrome on on Android prior to 156.0.8078.47 allowed a remote attacker who had compromi…
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High 8.8
Race condition in OptimizationGuide in Google Chrome prior to 156.0.8078.47 allowed a remote attacker to leak sensitive…
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High 8.8
Race condition in DevTools in Google Chrome prior to 156.0.8078.47 allowed a remote attacker who had compromised the re…
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High 8.8
Race condition in Actor in Google Chrome prior to 156.0.8078.47 allowed a remote attacker leveraging social engineering…
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Medium 6.5
Race condition in Installer in Google Chrome on on Mac prior to 156.0.8078.47 allowed a local attacker to execute arbit…
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High 8.8
Race condition in Toolbar in Google Chrome on on Android prior to 156.0.8078.47 allowed a remote attacker leveraging so…
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High 8.8
Race condition in Extensions in Google Chrome prior to 156.0.8078.47 allowed a remote attacker leveraging social engine…
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High 8.8
Race condition in DataTransfer in Google Chrome prior to 156.0.8078.47 allowed a remote attacker who had compromised th…
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High 8.8
Race condition in Transactions Platform in Google Chrome prior to 156.0.8078.47 allowed a remote attacker who had compr…
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High 8.8
Race condition in Extensions in Google Chrome prior to 156.0.8078.47 allowed a remote attacker leveraging social engine…
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Medium 6.5
Race condition in Mobile in Google Chrome on on iOS prior to 156.0.8078.47 allowed a remote attacker to spoof UI elemen…
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High 8.8
Race condition in SiteIsolation in Google Chrome on on Android prior to 156.0.8078.47 allowed a remote attacker to obta…
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Medium 6.5
Race condition in Extensions in Google Chrome prior to 156.0.8078.47 allowed a remote attacker leveraging social engine…
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Critical 9.6
Race condition in Compositing in Google Chrome prior to 156.0.8078.47 allowed a remote attacker who had compromised the…
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High 8.8
Race condition in Voice in Google Chrome on on Android prior to 156.0.8078.47 allowed a local attacker to bypass system…
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High 8.8
Race condition in Transactions Platform in Google Chrome prior to 156.0.8078.47 allowed a remote attacker who had compr…
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Low 3.3
filelock: SoftReadWriteLock follows a lock tree swapped in after its first acquire and writes lock records into directories of the user running the lock
filelock is a platform-independent file lock for Python. From 4.1.0 until 4.2.1, SoftReadWriteLock and AsyncSoftReadWriteLock cache a successful check of the <path>.rw lock tree and resolve its names again during later record operations, allowing another loca…
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Medium 6.1
filelock: ReadWriteLock on the hard-link route deletes any directory another user renames onto its .filelock-* link directory name
filelock is a platform-independent file lock for Python. From 4.1.0 until 4.2.1, ReadWriteLock can remove a randomized .filelock-* private-hard-link directory during cleanup, allowing another local user with rename access in a non-sticky parent to observe a l…
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Medium 4.7
filelock: SoftFileLock stale-lock break removes a live lock file on a reused inode number and admits two holders
filelock is a platform-independent file lock for Python. From 3.22.0 until 4.2.1, SoftFileLock can break a stale marker after an attacker frees its own marker following the stale read, an honest contender creates a live successor on the reused inode, and the …
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High 8.1
Apache Tomcat: TOCTOU when setting specific permissions for Unix Domain Sockets - Fix for CVE-2026-65183 did not address APR connector
Time-of-check time-of-use (TOCTOU) race condition vulnerability in Apache Tomcat when creating unix domain sockets for the APR/Native connector allows an unauthorised local user to access the unix domain socket. The fix for CVE-2026-65183 only addressed the N…
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Medium 6.3
AliasVault: Server-Side Request Forgery via DNS rebinding in Favicon Extraction
AliasVault is a privacy-first password manager with built-in email aliasing. Prior to 0.30.3, the AliasVault server API favicon extractor validates a user-supplied hostname with a first DNS lookup but allows the HTTP client to perform a second DNS lookup when…
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Low 2.3
Lychee: Distinct post-fix SSRF variant in Photo::fromUrl due to missing IP pinning after DNS-based validation
Lychee is a free, open-source photo-management tool. Prior to 7.6.0, the POST /api/v2/Photo::fromUrl flow validates a hostname and its resolved addresses in app/Rules/PhotoUrlRule.php but later passes the original hostname through app/Actions/Import/FromUrl.p…
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Medium 5.5
TOCTOU race between sound(4) buffer resizing and mmap
When an audio channel's buffer needs to be resized, the sound(4) driver checks that the buffer is not memory-mapped and then drops the channel lock to allocate a new buffer. An mmap(2) call on another thread can complete during this window, after which the re…
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High 7.5
vcs_pentest Race Condition Authentication Bypass Vulnerability in QuRouter management interface
A time-of-check time-of-use (toctou) race condition vulnerability has been reported to affect QuRouter. If exploited, the vulnerability could allow remote attackers to compromise the security of the system. We have already fixed the vulnerability in the follo…
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Medium 6.8
BentoPDF: SSRF via DNS Rebinding (TOCTOU) in Cloudflare CORS Proxy Worker
BentoPDF is a privacy-focused PDF toolkit that runs in the browser. In versions through 2.8.6, cloudflare/cors-proxy-worker.js performs a DNS-over-HTTPS safety check in hostnameResolvesToPrivate(), as used by isValidCertificateUrl() and isValidTsaUrl(), separ…