CWE-208
AllowedObservable Timing Discrepancy
Abstraction: Base · Status: Incomplete
Two separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not.
305 vulnerabilities reference this CWE, most recent first.
GHSA-XFQG-P48G-HH94
Vulnerability from github – Published: 2022-06-02 21:02 – Updated: 2022-06-02 21:02Ibexa DXP is using random execution time to hinder timing attacks against user accounts, a method of discovering whether a given account exists in a system without knowing its password, thus affecting privacy. This implementation was found to not be good enough in some situations. The fix replaces this with constant time functionality, configured in the new security.yml parameter 'ibexa.security.authentication.constant_auth_time'. It will log a warning if the constant time is exceeded. If this happens the setting should be increased.
{
"affected": [
{
"package": {
"ecosystem": "Packagist",
"name": "ezsystems/ezpublish-kernel"
},
"ranges": [
{
"events": [
{
"introduced": "7.5.0"
},
{
"fixed": "7.5.29"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": true,
"github_reviewed_at": "2022-06-02T21:02:00Z",
"nvd_published_at": null,
"severity": "CRITICAL"
},
"details": "Ibexa DXP is using random execution time to hinder timing attacks against user accounts, a method of discovering whether a given account exists in a system without knowing its password, thus affecting privacy. This implementation was found to not be good enough in some situations. The fix replaces this with constant time functionality, configured in the new security.yml parameter \u0027ibexa.security.authentication.constant_auth_time\u0027. It will log a warning if the constant time is exceeded. If this happens the setting should be increased.",
"id": "GHSA-xfqg-p48g-hh94",
"modified": "2022-06-02T21:02:00Z",
"published": "2022-06-02T21:02:00Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/ezsystems/ezpublish-kernel/security/advisories/GHSA-xfqg-p48g-hh94"
},
{
"type": "WEB",
"url": "https://github.com/ezsystems/ezpublish-kernel/commit/913fe17281536a91437d94e8267181ae8b57f5d5"
},
{
"type": "WEB",
"url": "https://developers.ibexa.co/security-advisories/ibexa-sa-2022-006-vulnerabilities-in-page-builder-login-and-commerce"
},
{
"type": "PACKAGE",
"url": "https://github.com/ezsystems/ezpublish-kernel"
},
{
"type": "WEB",
"url": "https://issues.ibexa.co/browse/IBX-1755"
}
],
"schema_version": "1.4.0",
"severity": [],
"summary": "Login timing attack in ezsystems/ezpublish-kernel"
}
GHSA-XG4X-W2J3-57H6
Vulnerability from github – Published: 2026-01-27 18:33 – Updated: 2026-02-02 16:33Impact
OctoPrint versions up to and including 1.11.5 are affected by a (theoretical) timing attack vulnerability that allows API key extraction over the network.
Due to using character based comparison that short-circuits on the first mismatched character during API key validation, rather than a cryptographical method with static runtime regardless of the point of mismatch, an attacker with network based access to an affected OctoPrint could extract API keys valid on the instance by measuring the response times of the denied access responses and guess an API key character by character.
Patches
The vulnerability will be patched in version 1.11.6.
Workaround
The likelihood of this attack actually working is highly dependent on the network's latency, noise and similar parameters. An actual proof of concept was not achieved so far. Still, as always administrators are advised to not expose their OctoPrint instance on hostile networks, especially not on the public Internet!
Credits
This vulnerability was discovered and responsibly disclosed to OctoPrint by Knox Liu.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "OctoPrint"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.11.6"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-23892"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": true,
"github_reviewed_at": "2026-01-27T18:33:50Z",
"nvd_published_at": "2026-01-27T19:16:16Z",
"severity": "MODERATE"
},
"details": "### Impact\n\nOctoPrint versions up to and including 1.11.5 are affected by a (theoretical) timing attack vulnerability that allows API key extraction over the network.\n\nDue to using character based comparison that short-circuits on the first mismatched character during API key validation, rather than a cryptographical method with static runtime regardless of the point of mismatch, an attacker with network based access to an affected OctoPrint could extract API keys valid on the instance by measuring the response times of the denied access responses and guess an API key character by character.\n\n### Patches\n\nThe vulnerability will be patched in version 1.11.6.\n\n### Workaround\n\nThe likelihood of this attack actually working is highly dependent on the network\u0027s latency, noise and similar parameters. An actual proof of concept was not achieved so far. Still, as always administrators are advised to not expose their OctoPrint instance on hostile networks, especially not on the public Internet!\n\n### Credits\n\nThis vulnerability was discovered and responsibly disclosed to OctoPrint by [Knox Liu](https://github.com/yueyueL).",
"id": "GHSA-xg4x-w2j3-57h6",
"modified": "2026-02-02T16:33:31Z",
"published": "2026-01-27T18:33:50Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/OctoPrint/OctoPrint/security/advisories/GHSA-xg4x-w2j3-57h6"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23892"
},
{
"type": "WEB",
"url": "https://github.com/OctoPrint/OctoPrint/commit/249fd80ab01bc4b7dabedff768230a0fb5d01a8c"
},
{
"type": "PACKAGE",
"url": "https://github.com/OctoPrint/OctoPrint"
},
{
"type": "WEB",
"url": "https://github.com/OctoPrint/OctoPrint/releases/tag/1.11.6"
}
],
"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"
},
{
"score": "CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "OctoPrint has Timing Side-Channel Vulnerability in API Key Authentication"
}
GHSA-XJHR-FM27-4HMX
Vulnerability from github – Published: 2026-02-25 18:31 – Updated: 2026-02-26 22:50An issue in OpenFUN Richie (LMS) in src/richie/apps/courses/api.py. The application used the non-constant time == operator for HMAC signature verification in the sync_course_run_from_request function. This allows remote attackers to forge valid signatures and bypass authentication by measuring response time discrepancies.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "richie"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-26717"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": true,
"github_reviewed_at": "2026-02-26T22:50:20Z",
"nvd_published_at": "2026-02-25T17:25:39Z",
"severity": "MODERATE"
},
"details": "An issue in OpenFUN Richie (LMS) in src/richie/apps/courses/api.py. The application used the non-constant time == operator for HMAC signature verification in the sync_course_run_from_request function. This allows remote attackers to forge valid signatures and bypass authentication by measuring response time discrepancies.",
"id": "GHSA-xjhr-fm27-4hmx",
"modified": "2026-02-26T22:50:20Z",
"published": "2026-02-25T18:31:38Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-26717"
},
{
"type": "WEB",
"url": "https://github.com/openfun/richie/commit/a1b5bbda3403d7debb466c303a32852925fcba5f"
},
{
"type": "WEB",
"url": "https://github.com/Rickidevs/CVE-2026-26717"
},
{
"type": "PACKAGE",
"url": "https://github.com/openfun/richie"
},
{
"type": "WEB",
"url": "https://medium.com/@ordogh/cve-2026-26717-hmac-timing-attack-in-openfun-richie-lms-f04377efe83d?postPublishedType=repub"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "OpenFUN Richie Observable Timing Discrepancy in its sync_course_run_from_request function"
}
GHSA-XR3W-RMVJ-F6M7
Vulnerability from github – Published: 2025-10-16 09:30 – Updated: 2025-10-16 21:04Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to use constant-time comparison for sensitive string comparisons which allows attackers to exploit timing oracles to perform byte-by-byte brute force attacks via response time analysis on Cloud API keys and OAuth client secrets.
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/mattermost/mattermost/server/v8"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "8.0.0-20250728063359-38208b8f065f"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/mattermost/mattermost-server"
},
"ranges": [
{
"events": [
{
"introduced": "10.5.0"
},
{
"fixed": "10.5.11"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/mattermost/mattermost-server"
},
"ranges": [
{
"events": [
{
"introduced": "10.11.0"
},
{
"fixed": "10.11.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-54499"
],
"database_specific": {
"cwe_ids": [
"CWE-208"
],
"github_reviewed": true,
"github_reviewed_at": "2025-10-16T21:04:21Z",
"nvd_published_at": "2025-10-16T09:15:34Z",
"severity": "LOW"
},
"details": "Mattermost versions 10.5.x \u003c= 10.5.10, 10.11.x \u003c= 10.11.2 fail to use constant-time comparison for sensitive string comparisons which allows attackers to exploit timing oracles to perform byte-by-byte brute force attacks via response time analysis on Cloud API keys and OAuth client secrets.",
"id": "GHSA-xr3w-rmvj-f6m7",
"modified": "2025-10-16T21:04:21Z",
"published": "2025-10-16T09:30:24Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-54499"
},
{
"type": "WEB",
"url": "https://github.com/mattermost/mattermost/commit/38208b8f065f0786eac0e968f9d754b91b62878c"
},
{
"type": "WEB",
"url": "https://github.com/mattermost/mattermost/commit/97a4c7839cf5610cfe17c52042878aebb7678372"
},
{
"type": "PACKAGE",
"url": "https://github.com/mattermost/mattermost"
},
{
"type": "WEB",
"url": "https://mattermost.com/security-updates"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "Mattermost has an Observable Timing Discrepancy vulnerability"
}
GHSA-XWG3-QRCG-W9X6
Vulnerability from github – Published: 2021-04-19 14:51 – Updated: 2021-04-23 17:17Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:flow-server versions 1.0.0 through 1.0.13 (Vaadin 10.0.0 through 10.0.16), 1.1.0 prior to 2.0.0 (Vaadin 11 through 13), 2.0.0 through 2.4.6 (Vaadin 14.0.0 through 14.4.6), 3.0.0 prior to 5.0.0 (Vaadin 15 prior to 18), and 5.0.0 through 5.0.2 (Vaadin 18.0.0 through 18.0.5) allows attacker to guess a security token via timing attack.
- https://vaadin.com/security/cve-2021-31404
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "com.vaadin:flow-server"
},
"ranges": [
{
"events": [
{
"introduced": "1.0.0"
},
{
"fixed": "1.0.14"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "com.vaadin:flow-server"
},
"ranges": [
{
"events": [
{
"introduced": "1.1.0"
},
{
"fixed": "2.4.7"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "com.vaadin:flow-server"
},
"ranges": [
{
"events": [
{
"introduced": "3.0.0"
},
{
"fixed": "5.0.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2021-31404"
],
"database_specific": {
"cwe_ids": [
"CWE-203",
"CWE-208"
],
"github_reviewed": true,
"github_reviewed_at": "2021-04-16T23:16:19Z",
"nvd_published_at": "2021-04-23T16:15:00Z",
"severity": "MODERATE"
},
"details": "Non-constant-time comparison of CSRF tokens in UIDL request handler in `com.vaadin:flow-server` versions 1.0.0 through 1.0.13 (Vaadin 10.0.0 through 10.0.16), 1.1.0 prior to 2.0.0 (Vaadin 11 through 13), 2.0.0 through 2.4.6 (Vaadin 14.0.0 through 14.4.6), 3.0.0 prior to 5.0.0 (Vaadin 15 prior to 18), and 5.0.0 through 5.0.2 (Vaadin 18.0.0 through 18.0.5) allows attacker to guess a security token via timing attack.\n\n- https://vaadin.com/security/cve-2021-31404",
"id": "GHSA-xwg3-qrcg-w9x6",
"modified": "2021-04-23T17:17:16Z",
"published": "2021-04-19T14:51:25Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/vaadin/flow/security/advisories/GHSA-xwg3-qrcg-w9x6"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-31404"
},
{
"type": "WEB",
"url": "https://github.com/vaadin/flow/pull/9875"
},
{
"type": "WEB",
"url": "https://vaadin.com/security/cve-2021-31404"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Timing side channel vulnerability in UIDL request handler in Vaadin 10, 11-14, and 15-18"
}
No mitigation information available for this CWE.
CAPEC-462: Cross-Domain Search Timing
An attacker initiates cross domain HTTP / GET requests and times the server responses. The timing of these responses may leak important information on what is happening on the server. Browser's same origin policy prevents the attacker from directly reading the server responses (in the absence of any other weaknesses), but does not prevent the attacker from timing the responses to requests that the attacker issued cross domain.
CAPEC-541: Application Fingerprinting
An adversary engages in fingerprinting activities to determine the type or version of an application installed on a remote target.
CAPEC-580: System Footprinting
An adversary engages in active probing and exploration activities to determine security information about a remote target system. Often times adversaries will rely on remote applications that can be probed for system configurations.