CWE-362
Allowed-with-ReviewConcurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Abstraction: Class · Status: Draft
The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
2925 vulnerabilities reference this CWE, most recent first.
GHSA-9J75-Q276-C2HC
Vulnerability from github – Published: 2025-11-11 18:30 – Updated: 2025-11-11 18:30In JetBrains YouTrack before 2025.3.104432 a race condition allowed bypass of helpdesk Agent limit
{
"affected": [],
"aliases": [
"CVE-2025-64773"
],
"database_specific": {
"cwe_ids": [
"CWE-362"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-11-11T16:15:40Z",
"severity": "LOW"
},
"details": "In JetBrains YouTrack before 2025.3.104432 a race condition allowed bypass of helpdesk Agent limit",
"id": "GHSA-9j75-q276-c2hc",
"modified": "2025-11-11T18:30:17Z",
"published": "2025-11-11T18:30:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-64773"
},
{
"type": "WEB",
"url": "https://www.jetbrains.com/privacy-security/issues-fixed"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-9J8Q-M9X5-9G6J
Vulnerability from github – Published: 2021-08-25 20:59 – Updated: 2021-08-24 18:52An issue was discovered in the async-coap crate through 2020-12-08 for Rust.
Affected versions of this crate implement Send/Sync for ArcGuard<RC, T> with no trait bounds on RC. This allows users to send RC: !Send to other threads and also allows users to concurrently access Rc: !Sync from multiple threads.
This can result in memory corruption from data race or other undefined behavior caused by sending T: !Send to other threads (e.g. dropping MutexGuard<T> in another thread that didn't lock its mutex).
{
"affected": [
{
"package": {
"ecosystem": "crates.io",
"name": "async-coap"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "0.1.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2020-36444"
],
"database_specific": {
"cwe_ids": [
"CWE-119",
"CWE-362"
],
"github_reviewed": true,
"github_reviewed_at": "2021-08-09T21:45:44Z",
"nvd_published_at": "2021-08-08T06:15:00Z",
"severity": "HIGH"
},
"details": "An issue was discovered in the async-coap crate through 2020-12-08 for Rust. \nAffected versions of this crate implement Send/Sync for `ArcGuard\u003cRC, T\u003e` with no trait bounds on `RC`. This allows users to send `RC: !Send` to other threads and also allows users to concurrently access `Rc: !Sync` from multiple threads.\n\nThis can result in memory corruption from data race or other undefined behavior caused by sending `T: !Send` to other threads (e.g. dropping `MutexGuard\u003cT\u003e` in another thread that didn\u0027t lock its mutex).\n",
"id": "GHSA-9j8q-m9x5-9g6j",
"modified": "2021-08-24T18:52:16Z",
"published": "2021-08-25T20:59:11Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-36444"
},
{
"type": "WEB",
"url": "https://github.com/google/rust-async-coap/issues/33"
},
{
"type": "PACKAGE",
"url": "https://github.com/google/rust-async-coap"
},
{
"type": "WEB",
"url": "https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/async-coap/RUSTSEC-2020-0124.md"
},
{
"type": "WEB",
"url": "https://rustsec.org/advisories/RUSTSEC-2020-0124.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "Data races in async-coap"
}
GHSA-9J94-67JR-4CQJ
Vulnerability from github – Published: 2025-05-08 14:45 – Updated: 2025-05-09 14:34Summary
When using the Rack::Session::Pool middleware, simultaneous rack requests can restore a deleted rack session, which allows the unauthenticated user to occupy that session.
Details
Rack session middleware prepares the session at the beginning of request, then saves is back to the store with possible changes applied by host rack application. This way the session becomes to be a subject of race conditions in general sense over concurrent rack requests.
Impact
When using the Rack::Session::Pool middleware, and provided the attacker can acquire a session cookie (already a major issue), the session may be restored if the attacker can trigger a long running request (within that same session) adjacent to the user logging out, in order to retain illicit access even after a user has attempted to logout.
Mitigation
- Update to the latest version of
rack-session, or - Ensure your application invalidates sessions atomically by marking them as logged out e.g., using a
logged_outflag, instead of deleting them, and check this flag on every request to prevent reuse, or - Implement a custom session store that tracks session invalidation timestamps and refuses to accept session data if the session was invalidated after the request began.
Related
This code was previously part of rack in Rack < 3, see https://github.com/rack/rack/security/advisories/GHSA-vpfw-47h7-xj4g for the equivalent advisory in rack (affecting Rack < 3 only).
{
"affected": [
{
"package": {
"ecosystem": "RubyGems",
"name": "rack-session"
},
"ranges": [
{
"events": [
{
"introduced": "2.0.0"
},
{
"fixed": "2.1.1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-46336"
],
"database_specific": {
"cwe_ids": [
"CWE-362",
"CWE-367",
"CWE-613"
],
"github_reviewed": true,
"github_reviewed_at": "2025-05-08T14:45:33Z",
"nvd_published_at": "2025-05-08T20:15:30Z",
"severity": "MODERATE"
},
"details": "## Summary\n\nWhen using the `Rack::Session::Pool` middleware, simultaneous rack requests can restore a deleted rack session, which allows the unauthenticated user to occupy that session.\n\n## Details\n\n[Rack session middleware](https://github.com/rack/rack-session/blob/v2.1.0/lib/rack/session/abstract/id.rb#L271-L278) prepares the session at the beginning of request, then saves is back to the store with possible changes applied by host rack application. This way the session becomes to be a subject of race conditions in general sense over concurrent rack requests.\n\n## Impact\n\nWhen using the `Rack::Session::Pool` middleware, and provided the attacker can acquire a session cookie (already a major issue), the session may be restored if the attacker can trigger a long running request (within that same session) adjacent to the user logging out, in order to retain illicit access even after a user has attempted to logout.\n\n## Mitigation\n\n- Update to the latest version of `rack-session`, or\n- Ensure your application invalidates sessions atomically by marking them as logged out e.g., using a `logged_out` flag, instead of deleting them, and check this flag on every request to prevent reuse, or\n- Implement a custom session store that tracks session invalidation timestamps and refuses to accept session data if the session was invalidated after the request began.\n\n## Related\n\nThis code was previously part of `rack` in Rack \u003c 3, see \u003chttps://github.com/rack/rack/security/advisories/GHSA-vpfw-47h7-xj4g\u003e for the equivalent advisory in `rack` (affecting Rack \u003c 3 only).",
"id": "GHSA-9j94-67jr-4cqj",
"modified": "2025-05-09T14:34:48Z",
"published": "2025-05-08T14:45:33Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/rack/rack-session/security/advisories/GHSA-9j94-67jr-4cqj"
},
{
"type": "WEB",
"url": "https://github.com/rack/rack/security/advisories/GHSA-vpfw-47h7-xj4g"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-46336"
},
{
"type": "WEB",
"url": "https://github.com/rack/rack-session/commit/c28c4a8c1861d814e09f2ae48264ac4c40be2d3b"
},
{
"type": "PACKAGE",
"url": "https://github.com/rack/rack-session"
},
{
"type": "WEB",
"url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/rack-session/CVE-2025-46336.yml"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Rack session gets restored after deletion"
}
GHSA-9JJV-35HV-G56W
Vulnerability from github – Published: 2022-05-17 01:26 – Updated: 2022-05-17 01:26parcimonie before 0.8.1, when using a large keyring, sleeps for the same amount of time between fetches, which allows attackers to correlate key fetches via unspecified vectors.
{
"affected": [],
"aliases": [
"CVE-2014-1921"
],
"database_specific": {
"cwe_ids": [
"CWE-362"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2014-02-14T15:55:00Z",
"severity": "HIGH"
},
"details": "parcimonie before 0.8.1, when using a large keyring, sleeps for the same amount of time between fetches, which allows attackers to correlate key fetches via unspecified vectors.",
"id": "GHSA-9jjv-35hv-g56w",
"modified": "2022-05-17T01:26:47Z",
"published": "2022-05-17T01:26:47Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2014-1921"
},
{
"type": "WEB",
"url": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=738134"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/91118"
},
{
"type": "WEB",
"url": "https://gaffer.ptitcanardnoir.org/intrigeri/files/parcimonie/App-Parcimonie-0.8.1.tar.gz"
},
{
"type": "WEB",
"url": "http://seclists.org/oss-sec/2014/q1/305"
},
{
"type": "WEB",
"url": "http://seclists.org/oss-sec/2014/q1/308"
},
{
"type": "WEB",
"url": "http://www.debian.org/security/2014/dsa-2860"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/65505"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-9JXP-4R84-XF98
Vulnerability from github – Published: 2022-05-13 01:23 – Updated: 2022-05-13 01:23Race condition in the ext4_file_write_iter function in fs/ext4/file.c in the Linux kernel through 3.17 allows local users to cause a denial of service (file unavailability) via a combination of a write action and an F_SETFL fcntl operation for the O_DIRECT flag.
{
"affected": [],
"aliases": [
"CVE-2014-8086"
],
"database_specific": {
"cwe_ids": [
"CWE-362"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2014-10-13T10:55:00Z",
"severity": "MODERATE"
},
"details": "Race condition in the ext4_file_write_iter function in fs/ext4/file.c in the Linux kernel through 3.17 allows local users to cause a denial of service (file unavailability) via a combination of a write action and an F_SETFL fcntl operation for the O_DIRECT flag.",
"id": "GHSA-9jxp-4r84-xf98",
"modified": "2022-05-13T01:23:24Z",
"published": "2022-05-13T01:23:24Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2014-8086"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=1151353"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/96922"
},
{
"type": "WEB",
"url": "https://lkml.org/lkml/2014/10/8/545"
},
{
"type": "WEB",
"url": "https://lkml.org/lkml/2014/10/9/129"
},
{
"type": "WEB",
"url": "http://lists.opensuse.org/opensuse-security-announce/2015-09/msg00004.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2015-0290.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2015-0694.html"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2014/10/09/25"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/70376"
},
{
"type": "WEB",
"url": "http://www.spinics.net/lists/linux-ext4/msg45683.html"
},
{
"type": "WEB",
"url": "http://www.spinics.net/lists/linux-ext4/msg45685.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-9M59-V99V-J834
Vulnerability from github – Published: 2026-07-14 18:32 – Updated: 2026-07-14 18:32Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Runtime allows an authorized attacker to elevate privileges locally.
{
"affected": [],
"aliases": [
"CVE-2026-50385"
],
"database_specific": {
"cwe_ids": [
"CWE-362"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-14T18:17:40Z",
"severity": "HIGH"
},
"details": "Concurrent execution using shared resource with improper synchronization (\u0027race condition\u0027) in Windows Runtime allows an authorized attacker to elevate privileges locally.",
"id": "GHSA-9m59-v99v-j834",
"modified": "2026-07-14T18:32:19Z",
"published": "2026-07-14T18:32:19Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-50385"
},
{
"type": "WEB",
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50385"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-9M98-937V-R97X
Vulnerability from github – Published: 2024-07-17 00:32 – Updated: 2024-08-01 15:32Race in DevTools in Google Chrome prior to 126.0.6478.182 allowed an attacker who convinced a user to install a malicious extension to inject scripts or HTML into a privileged page via a crafted Chrome Extension. (Chromium security severity: High)
{
"affected": [],
"aliases": [
"CVE-2024-6778"
],
"database_specific": {
"cwe_ids": [
"CWE-362",
"CWE-366"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-07-16T22:15:07Z",
"severity": "HIGH"
},
"details": "Race in DevTools in Google Chrome prior to 126.0.6478.182 allowed an attacker who convinced a user to install a malicious extension to inject scripts or HTML into a privileged page via a crafted Chrome Extension. (Chromium security severity: High)",
"id": "GHSA-9m98-937v-r97x",
"modified": "2024-08-01T15:32:03Z",
"published": "2024-07-17T00:32:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-6778"
},
{
"type": "WEB",
"url": "https://chromereleases.googleblog.com/2024/07/stable-channel-update-for-desktop.html"
},
{
"type": "WEB",
"url": "https://issues.chromium.org/issues/341136300"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-9MHQ-XCRQ-XC75
Vulnerability from github – Published: 2023-05-10 00:30 – Updated: 2024-04-04 03:58An authentication bypass vulnerability exists in Avalanche versions 6.3.x and below that could allow an attacker to gain access by exploiting the SetUser method or can exploit the Race Condition in the authentication message.
{
"affected": [],
"aliases": [
"CVE-2023-28126"
],
"database_specific": {
"cwe_ids": [
"CWE-305",
"CWE-362"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-05-09T22:15:09Z",
"severity": "MODERATE"
},
"details": "An authentication bypass vulnerability exists in Avalanche versions 6.3.x and below that could allow an attacker to gain access by exploiting the SetUser method or can exploit the Race Condition in the authentication message.",
"id": "GHSA-9mhq-xcrq-xc75",
"modified": "2024-04-04T03:58:08Z",
"published": "2023-05-10T00:30:15Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-28126"
},
{
"type": "WEB",
"url": "https://forums.ivanti.com/s/article/ZDI-CAN-17750-Ivanti-Avalanche-EnterpriseServer-GetSettings-Exposed-Dangerous-Method-Authentication-Bypass-Vulnerability?language=en_US"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-9MVW-9C9Q-7CMM
Vulnerability from github – Published: 2021-12-09 00:00 – Updated: 2022-03-17 00:06By misusing a race in our notification code, an attacker could have forcefully hidden the notification for pages that had received full screen and pointer lock access, which could have been used for spoofing attacks. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.
{
"affected": [],
"aliases": [
"CVE-2021-43538"
],
"database_specific": {
"cwe_ids": [
"CWE-362"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-12-08T22:15:00Z",
"severity": "MODERATE"
},
"details": "By misusing a race in our notification code, an attacker could have forcefully hidden the notification for pages that had received full screen and pointer lock access, which could have been used for spoofing attacks. This vulnerability affects Thunderbird \u003c 91.4.0, Firefox ESR \u003c 91.4.0, and Firefox \u003c 95.",
"id": "GHSA-9mvw-9c9q-7cmm",
"modified": "2022-03-17T00:06:35Z",
"published": "2021-12-09T00:00:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-43538"
},
{
"type": "WEB",
"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1739091"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2021/12/msg00030.html"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html"
},
{
"type": "WEB",
"url": "https://security.gentoo.org/glsa/202202-03"
},
{
"type": "WEB",
"url": "https://security.gentoo.org/glsa/202208-14"
},
{
"type": "WEB",
"url": "https://www.debian.org/security/2021/dsa-5026"
},
{
"type": "WEB",
"url": "https://www.debian.org/security/2022/dsa-5034"
},
{
"type": "WEB",
"url": "https://www.mozilla.org/security/advisories/mfsa2021-52"
},
{
"type": "WEB",
"url": "https://www.mozilla.org/security/advisories/mfsa2021-53"
},
{
"type": "WEB",
"url": "https://www.mozilla.org/security/advisories/mfsa2021-54"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-9MWC-354M-HG9C
Vulnerability from github – Published: 2025-01-28 00:32 – Updated: 2025-11-03 21:32A race condition was addressed with additional validation. This issue is fixed in macOS Ventura 13.7.3, macOS Sequoia 15.3, macOS Sonoma 14.7.3. An app may be able to access user-sensitive data.
{
"affected": [],
"aliases": [
"CVE-2025-24094"
],
"database_specific": {
"cwe_ids": [
"CWE-362"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-01-27T22:15:15Z",
"severity": "MODERATE"
},
"details": "A race condition was addressed with additional validation. This issue is fixed in macOS Ventura 13.7.3, macOS Sequoia 15.3, macOS Sonoma 14.7.3. An app may be able to access user-sensitive data.",
"id": "GHSA-9mwc-354m-hg9c",
"modified": "2025-11-03T21:32:24Z",
"published": "2025-01-28T00:32:13Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-24094"
},
{
"type": "WEB",
"url": "https://support.apple.com/en-us/122068"
},
{
"type": "WEB",
"url": "https://support.apple.com/en-us/122069"
},
{
"type": "WEB",
"url": "https://support.apple.com/en-us/122070"
},
{
"type": "WEB",
"url": "http://seclists.org/fulldisclosure/2025/Jan/15"
},
{
"type": "WEB",
"url": "http://seclists.org/fulldisclosure/2025/Jan/16"
},
{
"type": "WEB",
"url": "http://seclists.org/fulldisclosure/2025/Jan/17"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
Mitigation
In languages that support it, use synchronization primitives. Only wrap these around critical code to minimize the impact on performance.
Mitigation
Use thread-safe capabilities such as the data access abstraction in Spring.
Mitigation
- Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring.
- Additionally, this will minimize the amount of synchronization necessary and may even help to reduce the likelihood of a denial of service where an attacker may be able to repeatedly trigger a critical section (CWE-400).
Mitigation
When using multithreading and operating on shared variables, only use thread-safe functions.
Mitigation
Use atomic operations on shared variables. Be wary of innocent-looking constructs such as "x++". This may appear atomic at the code layer, but it is actually non-atomic at the instruction layer, since it involves a read, followed by a computation, followed by a write.
Mitigation
Use a mutex if available, but be sure to avoid related weaknesses such as CWE-412.
Mitigation
Avoid double-checked locking (CWE-609) and other implementation errors that arise when trying to avoid the overhead of synchronization.
Mitigation
Disable interrupts or signals over critical parts of the code, but also make sure that the code does not go into a large or infinite loop.
Mitigation
Use the volatile type modifier for critical variables to avoid unexpected compiler optimization or reordering. This does not necessarily solve the synchronization problem, but it can help.
Mitigation MIT-17
Strategy: Environment Hardening
Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
CAPEC-26: Leveraging Race Conditions
The adversary targets a race condition occurring when multiple processes access and manipulate the same resource concurrently, and the outcome of the execution depends on the particular order in which the access takes place. The adversary can leverage a race condition by "running the race", modifying the resource and modifying the normal execution flow. For instance, a race condition can occur while accessing a file: the adversary can trick the system by replacing the original file with their version and cause the system to read the malicious 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.