CWE-400
DiscouragedUncontrolled Resource Consumption
Abstraction: Class · Status: Draft
The product does not properly control the allocation and maintenance of a limited resource.
6410 vulnerabilities reference this CWE, most recent first.
GHSA-283W-JXHF-PMRJ
Vulnerability from github – Published: 2025-09-16 21:31 – Updated: 2025-09-17 18:31The /api/comment endpoint in zhangyd-c OneBlog 2.3.9 contains a denial-of-service vulnerability.
{
"affected": [],
"aliases": [
"CVE-2025-56264"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-16T20:15:36Z",
"severity": "HIGH"
},
"details": "The /api/comment endpoint in zhangyd-c OneBlog 2.3.9 contains a denial-of-service vulnerability.",
"id": "GHSA-283w-jxhf-pmrj",
"modified": "2025-09-17T18:31:17Z",
"published": "2025-09-16T21:31:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-56264"
},
{
"type": "WEB",
"url": "https://github.com/echo0d/vulnerability/blob/main/zhangyd-c_OneBlog/DoS.md"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-2883-XCG3-V3HH
Vulnerability from github – Published: 2026-09-08 21:24 – Updated: 2026-09-08 21:24Summary
maxTotalMergeKeys does not count empty mappings. An attacker can repeatedly merge a large sequence of them and consume significant CPU without reaching the configured limit.
Example
arr: &arr [{}, {}, {}, ...] # N empty mappings
targets:
- <<: *arr # repeated K times
For every target, the loader iterates all N elements of arr. This results in O(N * K) work while totalMergeKeys remains unchanged.
PoC
import { performance } from 'node:perf_hooks'
import { load, YAML11_SCHEMA } from 'js-yaml'
const n = 20000
const src =
'arr: &arr [' + '{},'.repeat(n).slice(0, -1) + ']\n' +
'targets:\n' +
' - <<: *arr\n'.repeat(n)
const started = performance.now()
load(src, { schema: YAML11_SCHEMA })
console.log(`${(performance.now() - started).toFixed(1)} ms`)
Observed results:
| N | YAML size | Time |
|---|---|---|
| 800 | ~13 KB | ~20 ms |
| 3200 | ~50 KB | ~180 ms |
| 20000 | ~500 KB | ~13 s |
Impact
An attacker can submit a relatively small YAML document that causes prolonged CPU consumption despite the default maxTotalMergeKeys limit.
Fix
Count each merge-source mapping as one budget unit, in addition to counting its keys.
Difference with v5
In v3 & v4, merge is enabled by default. So, the severity score is higher.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "js-yaml"
},
"ranges": [
{
"events": [
{
"introduced": "4.0.0"
},
{
"fixed": "4.3.2"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "js-yaml"
},
"ranges": [
{
"events": [
{
"introduced": "3.0.0"
},
{
"fixed": "3.15.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-84375"
],
"database_specific": {
"cwe_ids": [
"CWE-400",
"CWE-407"
],
"github_reviewed": true,
"github_reviewed_at": "2026-09-08T21:24:51Z",
"nvd_published_at": "2026-09-01T22:17:19Z",
"severity": "HIGH"
},
"details": "## Summary\n\n`maxTotalMergeKeys` does not count empty mappings. An attacker can repeatedly merge a large sequence of them and consume significant CPU without reaching the configured limit.\n\n## Example\n\n```yaml\narr: \u0026arr [{}, {}, {}, ...] # N empty mappings\ntargets:\n - \u003c\u003c: *arr # repeated K times\n```\n\nFor every target, the loader iterates all `N` elements of `arr`. This results in `O(N * K)` work while `totalMergeKeys` remains unchanged.\n\n## PoC\n\n```js\nimport { performance } from \u0027node:perf_hooks\u0027\nimport { load, YAML11_SCHEMA } from \u0027js-yaml\u0027\n\nconst n = 20000\n\nconst src =\n \u0027arr: \u0026arr [\u0027 + \u0027{},\u0027.repeat(n).slice(0, -1) + \u0027]\\n\u0027 +\n \u0027targets:\\n\u0027 +\n \u0027 - \u003c\u003c: *arr\\n\u0027.repeat(n)\n\nconst started = performance.now()\n\nload(src, { schema: YAML11_SCHEMA })\n\nconsole.log(`${(performance.now() - started).toFixed(1)} ms`)\n```\n\nObserved results:\n\n| N | YAML size | Time |\n|---:|---:|---:|\n| 800 | ~13 KB | ~20 ms |\n| 3200 | ~50 KB | ~180 ms |\n| 20000 | ~500 KB | ~13 s |\n\n## Impact\n\nAn attacker can submit a relatively small YAML document that causes prolonged CPU consumption despite the default `maxTotalMergeKeys` limit.\n\n## Fix\n\nCount each merge-source mapping as one budget unit, in addition to counting its keys.\n\n## Difference with v5\n\nIn v3 \u0026 v4, merge is enabled by default. So, the severity score is higher.",
"id": "GHSA-2883-xcg3-v3hh",
"modified": "2026-09-08T21:24:51Z",
"published": "2026-09-08T21:24:51Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/nodeca/js-yaml/security/advisories/GHSA-2883-xcg3-v3hh"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84375"
},
{
"type": "WEB",
"url": "https://github.com/nodeca/js-yaml/pull/797"
},
{
"type": "WEB",
"url": "https://github.com/nodeca/js-yaml/commit/3485bc06ff8a0251505f44a00414d90df2466639"
},
{
"type": "WEB",
"url": "https://github.com/nodeca/js-yaml/commit/6a8e05f9a485188ed730ac81e81ae221352ef480"
},
{
"type": "WEB",
"url": "https://github.com/nodeca/js-yaml/commit/d90b6612a5a84385bdcb556c44578eac76dc0f6b"
},
{
"type": "PACKAGE",
"url": "https://github.com/nodeca/js-yaml"
},
{
"type": "WEB",
"url": "https://github.com/nodeca/js-yaml/releases/tag/3.15.2"
},
{
"type": "WEB",
"url": "https://github.com/nodeca/js-yaml/releases/tag/4.3.2"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
],
"summary": "js-yaml: maxTotalMergeKeys does not limit CPU use for empty merge sources"
}
GHSA-28J9-FQ4C-QRQG
Vulnerability from github – Published: 2024-06-13 00:31 – Updated: 2024-06-13 00:31An issue has been discovered in GitLab CE/EE affecting all versions prior to 16.10.7, starting from 16.11 prior to 16.11.4, and starting from 17.0 prior to 17.0.2. A vulnerability in GitLab's CI/CD pipeline editor could allow for denial of service attacks through maliciously crafted configuration files.
{
"affected": [],
"aliases": [
"CVE-2024-1736"
],
"database_specific": {
"cwe_ids": [
"CWE-1333",
"CWE-400"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-06-12T23:15:49Z",
"severity": "MODERATE"
},
"details": "An issue has been discovered in GitLab CE/EE affecting all versions prior to 16.10.7, starting from 16.11 prior to 16.11.4, and starting from 17.0 prior to 17.0.2. A vulnerability in GitLab\u0027s CI/CD pipeline editor could allow for denial of service attacks through maliciously crafted configuration files.",
"id": "GHSA-28j9-fq4c-qrqg",
"modified": "2024-06-13T00:31:23Z",
"published": "2024-06-13T00:31:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-1736"
},
{
"type": "WEB",
"url": "https://hackerone.com/reports/2358689"
},
{
"type": "WEB",
"url": "https://about.gitlab.com/releases/2024/06/12/patch-release-gitlab-17-0-2-released/#redos-in-ci-interpolation-fix-bypass"
},
{
"type": "WEB",
"url": "https://gitlab.com/gitlab-org/gitlab/-/issues/442695"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-28MG-G63P-PFF3
Vulnerability from github – Published: 2026-08-21 00:31 – Updated: 2026-08-21 00:31IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to cause a denial of service due to uncontrolled resource consumption.
{
"affected": [],
"aliases": [
"CVE-2026-16952"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-20T22:17:09Z",
"severity": "MODERATE"
},
"details": "IBM AIX 7.2, and 7.3 and IBM PowerVM VIOS 4.1 could allow a local attacker to cause a denial of service due to uncontrolled resource consumption.",
"id": "GHSA-28mg-g63p-pff3",
"modified": "2026-08-21T00:31:19Z",
"published": "2026-08-21T00:31:19Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-16952"
},
{
"type": "WEB",
"url": "https://www.ibm.com/support/pages/node/7283858"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-2944-MCC5-RGM4
Vulnerability from github – Published: 2026-09-14 15:32 – Updated: 2026-09-14 15:32File Browser through 2.63.23 contains a memory exhaustion vulnerability in the subtitle conversion endpoint that loads entire subtitle files into memory without size limits. Authenticated attackers with download permission can request conversion of large .srt, .ass, or .ssa files and exhaust server memory through concurrent requests, causing denial of service.
{
"affected": [],
"aliases": [
"CVE-2026-90928"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-14T13:19:30Z",
"severity": "HIGH"
},
"details": "File Browser through 2.63.23 contains a memory exhaustion vulnerability in the subtitle conversion endpoint that loads entire subtitle files into memory without size limits. Authenticated attackers with download permission can request conversion of large .srt, .ass, or .ssa files and exhaust server memory through concurrent requests, causing denial of service.",
"id": "GHSA-2944-mcc5-rgm4",
"modified": "2026-09-14T15:32:44Z",
"published": "2026-09-14T15:32:44Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/filebrowser/filebrowser/security/advisories/GHSA-448h-jr2h-3vhp"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90928"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/file-browser-through-2.63.23-memory-exhaustion-via-subtitle-endpoint"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-295X-89H7-9WPM
Vulnerability from github – Published: 2025-06-22 21:30 – Updated: 2025-06-22 21:30A vulnerability has been found in MarkText up to 0.17.1 and classified as problematic. Affected by this vulnerability is the function getRecommendTitleFromMarkdownString of the file marktext/src/main/utils/index.js. The manipulation leads to inefficient regular expression complexity. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.
{
"affected": [],
"aliases": [
"CVE-2025-6492"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-06-22T20:15:19Z",
"severity": "MODERATE"
},
"details": "A vulnerability has been found in MarkText up to 0.17.1 and classified as problematic. Affected by this vulnerability is the function getRecommendTitleFromMarkdownString of the file marktext/src/main/utils/index.js. The manipulation leads to inefficient regular expression complexity. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.",
"id": "GHSA-295x-89h7-9wpm",
"modified": "2025-06-22T21:30:27Z",
"published": "2025-06-22T21:30:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-6492"
},
{
"type": "WEB",
"url": "https://github.com/marktext/marktext/pull/3952"
},
{
"type": "WEB",
"url": "https://github.com/mmmsssttt404/marktext/blob/c59b3ad423dfa082869933baf9f5d5c69bdcc560/test/unit/specs/match-electron-accelerator.spec.js#L155-L164"
},
{
"type": "WEB",
"url": "https://vuldb.com/?ctiid.313609"
},
{
"type": "WEB",
"url": "https://vuldb.com/?id.313609"
},
{
"type": "WEB",
"url": "https://vuldb.com/?submit.598208"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-296W-6QHQ-GF92
Vulnerability from github – Published: 2022-05-14 02:05 – Updated: 2024-09-18 15:57The default configuration for the file upload handling system in Django before 1.4.14, 1.5.x before 1.5.9, 1.6.x before 1.6.6, and 1.7 before release candidate 3 uses a sequential file name generation process when a file with a conflicting name is uploaded, which allows remote attackers to cause a denial of service (CPU consumption) by unloading a multiple files with the same name.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "Django"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.4.14"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "PyPI",
"name": "Django"
},
"ranges": [
{
"events": [
{
"introduced": "1.5"
},
{
"fixed": "1.5.9"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "PyPI",
"name": "Django"
},
"ranges": [
{
"events": [
{
"introduced": "1.6"
},
{
"fixed": "1.6.6"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2014-0481"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": true,
"github_reviewed_at": "2023-08-15T23:28:45Z",
"nvd_published_at": "2014-08-26T14:55:00Z",
"severity": "HIGH"
},
"details": "The default configuration for the file upload handling system in Django before 1.4.14, 1.5.x before 1.5.9, 1.6.x before 1.6.6, and 1.7 before release candidate 3 uses a sequential file name generation process when a file with a conflicting name is uploaded, which allows remote attackers to cause a denial of service (CPU consumption) by unloading a multiple files with the same name.",
"id": "GHSA-296w-6qhq-gf92",
"modified": "2024-09-18T15:57:34Z",
"published": "2022-05-14T02:05:08Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2014-0481"
},
{
"type": "WEB",
"url": "https://github.com/django/django/commit/26cd48e166ac4d84317c8ee6d63ac52a87e8da99"
},
{
"type": "WEB",
"url": "https://github.com/django/django/commit/30042d475bf084c6723c6217a21598d9247a9c41"
},
{
"type": "WEB",
"url": "https://github.com/django/django/commit/dd0c3f4ee1a30c1a1e6055061c6ba6e58c6b54d1"
},
{
"type": "PACKAGE",
"url": "https://github.com/django/django"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/django/PYSEC-2014-5.yaml"
},
{
"type": "WEB",
"url": "https://www.djangoproject.com/weblog/2014/aug/20/security"
},
{
"type": "WEB",
"url": "http://lists.opensuse.org/opensuse-updates/2014-09/msg00023.html"
},
{
"type": "WEB",
"url": "http://www.debian.org/security/2014/dsa-3010"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Django denial of service via file upload naming"
}
GHSA-2973-F65X-7J53
Vulnerability from github – Published: 2023-12-12 12:30 – Updated: 2023-12-15 15:30Denial-of-service (DoS) vulnerability exists in NetBIOS service of HMI GC-A2 series. If a remote unauthenticated attacker sends a specially crafted packets to specific ports, a denial-of-service (DoS) condition may occur.
{
"affected": [],
"aliases": [
"CVE-2023-49713"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-12-12T10:15:10Z",
"severity": "HIGH"
},
"details": "Denial-of-service (DoS) vulnerability exists in NetBIOS service of HMI GC-A2 series. If a remote unauthenticated attacker sends a specially crafted packets to specific ports, a denial-of-service (DoS) condition may occur.",
"id": "GHSA-2973-f65x-7j53",
"modified": "2023-12-15T15:30:21Z",
"published": "2023-12-12T12:30:52Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-49713"
},
{
"type": "WEB",
"url": "https://jvn.jp/en/jp/JVN34145838"
},
{
"type": "WEB",
"url": "https://www.electronics.jtekt.co.jp/en/topics/202312116562"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-297Q-7R2M-G586
Vulnerability from github – Published: 2022-05-14 03:35 – Updated: 2022-05-14 03:35In some circumstances, on F5 BIG-IP systems running 13.0.0, 12.1.0 - 12.1.3.1, any 11.6.x or 11.5.x release, or 11.2.1, TCP DNS profile allows excessive buffering due to lack of flow control.
{
"affected": [],
"aliases": [
"CVE-2018-5501"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2018-03-01T16:29:00Z",
"severity": "MODERATE"
},
"details": "In some circumstances, on F5 BIG-IP systems running 13.0.0, 12.1.0 - 12.1.3.1, any 11.6.x or 11.5.x release, or 11.2.1, TCP DNS profile allows excessive buffering due to lack of flow control.",
"id": "GHSA-297q-7r2m-g586",
"modified": "2022-05-14T03:35:56Z",
"published": "2022-05-14T03:35:56Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-5501"
},
{
"type": "WEB",
"url": "https://support.f5.com/csp/article/K44200194"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/103211"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-297Q-X8Q4-RP55
Vulnerability from github – Published: 2026-07-22 00:31 – Updated: 2026-07-22 00:31Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are MySQL Server: 9.7.0-9.7.1; MySQL Cluster: 9.7.0-9.7.1. Easily exploitable vulnerability allows low privileged attacker with network access via multiple protocols to compromise MySQL Server, MySQL Cluster. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server, MySQL Cluster. CVSS 3.1 Base Score 6.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H).
{
"affected": [],
"aliases": [
"CVE-2026-60174"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-21T22:17:18Z",
"severity": "MODERATE"
},
"details": "Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are MySQL Server: 9.7.0-9.7.1; MySQL Cluster: 9.7.0-9.7.1. Easily exploitable vulnerability allows low privileged attacker with network access via multiple protocols to compromise MySQL Server, MySQL Cluster. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server, MySQL Cluster. CVSS 3.1 Base Score 6.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H).",
"id": "GHSA-297q-x8q4-rp55",
"modified": "2026-07-22T00:31:21Z",
"published": "2026-07-22T00:31:21Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-60174"
},
{
"type": "WEB",
"url": "https://www.oracle.com/security-alerts/cpujul2026.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Mitigation
Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place. The login application should be protected against DoS attacks as much as possible. Limiting the database access, perhaps by caching result sets, can help minimize the resources expended. To further limit the potential for a DoS attack, consider tracking the rate of requests received from users and blocking requests that exceed a defined rate threshold.
Mitigation
- Mitigation of resource exhaustion attacks requires that the target system either:
- The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
- The second solution is simply difficult to effectively institute -- and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.
- recognizes the attack and denies that user further access for a given amount of time, or
- uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed.
Mitigation
Ensure that protocols have specific limits of scale placed on them.
Mitigation
Ensure that all failures in resource allocation place the system into a safe posture.
CAPEC-147: XML Ping of the Death
An attacker initiates a resource depletion attack where a large number of small XML messages are delivered at a sufficiently rapid rate to cause a denial of service or crash of the target. Transactions such as repetitive SOAP transactions can deplete resources faster than a simple flooding attack because of the additional resources used by the SOAP protocol and the resources necessary to process SOAP messages. The transactions used are immaterial as long as they cause resource utilization on the target. In other words, this is a normal flooding attack augmented by using messages that will require extra processing on the target.
CAPEC-227: Sustained Client Engagement
An adversary attempts to deny legitimate users access to a resource by continually engaging a specific resource in an attempt to keep the resource tied up as long as possible. The adversary's primary goal is not to crash or flood the target, which would alert defenders; rather it is to repeatedly perform actions or abuse algorithmic flaws such that a given resource is tied up and not available to a legitimate user. By carefully crafting a requests that keep the resource engaged through what is seemingly benign requests, legitimate users are limited or completely denied access to the resource.
CAPEC-492: Regular Expression Exponential Blowup
An adversary may execute an attack on a program that uses a poor Regular Expression(Regex) implementation by choosing input that results in an extreme situation for the Regex. A typical extreme situation operates at exponential time compared to the input size. This is due to most implementations using a Nondeterministic Finite Automaton(NFA) state machine to be built by the Regex algorithm since NFA allows backtracking and thus more complex regular expressions.