CWE-772
AllowedMissing Release of Resource after Effective Lifetime
Abstraction: Base · Status: Draft
The product does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed.
591 vulnerabilities reference this CWE, most recent first.
GHSA-WP6G-R7H4-VCWR
Vulnerability from github – Published: 2022-05-13 01:16 – Updated: 2022-05-13 01:16Memory leak in QEMU, when built with a VMWARE VMXNET3 paravirtual NIC emulator support, allows local guest users to cause a denial of service (host memory consumption) by trying to activate the vmxnet3 device repeatedly.
{
"affected": [],
"aliases": [
"CVE-2015-8568"
],
"database_specific": {
"cwe_ids": [
"CWE-772"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2017-04-11T19:59:00Z",
"severity": "MODERATE"
},
"details": "Memory leak in QEMU, when built with a VMWARE VMXNET3 paravirtual NIC emulator support, allows local guest users to cause a denial of service (host memory consumption) by trying to activate the vmxnet3 device repeatedly.",
"id": "GHSA-wp6g-r7h4-vcwr",
"modified": "2022-05-13T01:16:20Z",
"published": "2022-05-13T01:16:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2015-8568"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=1289816"
},
{
"type": "WEB",
"url": "https://lists.gnu.org/archive/html/qemu-devel/2015-12/msg02299.html"
},
{
"type": "WEB",
"url": "https://security.gentoo.org/glsa/201602-01"
},
{
"type": "WEB",
"url": "http://www.debian.org/security/2016/dsa-3471"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2015/12/15/10"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/79721"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-WP76-M554-XW7F
Vulnerability from github – Published: 2022-05-02 04:00 – Updated: 2022-05-02 04:00Memory leak in the gk_circuit_info_do_in_acf function in the H.323 implementation in Cisco IOS before 15.0(1)XA allows remote attackers to cause a denial of service (memory consumption) via a large number of calls over a long duration, as demonstrated by InterZone Clear Token (IZCT) test traffic, aka Bug ID CSCsz72535.
{
"affected": [],
"aliases": [
"CVE-2009-5039"
],
"database_specific": {
"cwe_ids": [
"CWE-772"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2011-01-07T19:00:00Z",
"severity": "MODERATE"
},
"details": "Memory leak in the gk_circuit_info_do_in_acf function in the H.323 implementation in Cisco IOS before 15.0(1)XA allows remote attackers to cause a denial of service (memory consumption) via a large number of calls over a long duration, as demonstrated by InterZone Clear Token (IZCT) test traffic, aka Bug ID CSCsz72535.",
"id": "GHSA-wp76-m554-xw7f",
"modified": "2022-05-02T04:00:46Z",
"published": "2022-05-02T04:00:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2009-5039"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/64731"
},
{
"type": "WEB",
"url": "http://www.cisco.com/en/US/docs/ios/15_0/15_0x/15_01_XA/rn800xa.pdf"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-WPH7-X527-W3H5
Vulnerability from github – Published: 2021-10-15 18:51 – Updated: 2024-03-11 16:36The fix for bug 63362 present in Apache Tomcat 10.1.0-M1 to 10.1.0-M5, 10.0.0-M1 to 10.0.11, 9.0.40 to 9.0.53 and 8.5.60 to 8.5.71 introduced a memory leak. The object introduced to collect metrics for HTTP upgrade connections was not released for WebSocket connections once the connection was closed. This created a memory leak that, over time, could lead to a denial of service via an OutOfMemoryError.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 10.1.0-M5"
},
"package": {
"ecosystem": "Maven",
"name": "org.apache.tomcat:tomcat"
},
"ranges": [
{
"events": [
{
"introduced": "10.1.0-M1"
},
{
"fixed": "10.1.0-M6"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.apache.tomcat:tomcat"
},
"ranges": [
{
"events": [
{
"introduced": "10.0.0-M1"
},
{
"fixed": "10.0.12"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.apache.tomcat:tomcat"
},
"ranges": [
{
"events": [
{
"introduced": "9.0.40"
},
{
"fixed": "9.0.54"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.apache.tomcat:tomcat"
},
"ranges": [
{
"events": [
{
"introduced": "8.5.60"
},
{
"fixed": "8.5.72"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2021-42340"
],
"database_specific": {
"cwe_ids": [
"CWE-772"
],
"github_reviewed": true,
"github_reviewed_at": "2021-10-15T13:59:01Z",
"nvd_published_at": "2021-10-14T20:15:00Z",
"severity": "HIGH"
},
"details": "The fix for bug 63362 present in Apache Tomcat 10.1.0-M1 to 10.1.0-M5, 10.0.0-M1 to 10.0.11, 9.0.40 to 9.0.53 and 8.5.60 to 8.5.71 introduced a memory leak. The object introduced to collect metrics for HTTP upgrade connections was not released for WebSocket connections once the connection was closed. This created a memory leak that, over time, could lead to a denial of service via an OutOfMemoryError.",
"id": "GHSA-wph7-x527-w3h5",
"modified": "2024-03-11T16:36:26Z",
"published": "2021-10-15T18:51:34Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-42340"
},
{
"type": "WEB",
"url": "https://github.com/apache/tomcat/commit/31d62426645824bdfe076a0c0eafa904d90b4fb9"
},
{
"type": "WEB",
"url": "https://github.com/apache/tomcat/commit/80f1438ec45e77a07b96419808971838d259eb47"
},
{
"type": "WEB",
"url": "https://github.com/apache/tomcat/commit/d27535bdee95d252418201eb21e9d29476aa6b6a"
},
{
"type": "WEB",
"url": "https://github.com/apache/tomcat/commit/d5a6660cba7f51589468937bf3bbad4db7810371"
},
{
"type": "WEB",
"url": "https://www.oracle.com/security-alerts/cpujul2022.html"
},
{
"type": "WEB",
"url": "https://www.oracle.com/security-alerts/cpujan2022.html"
},
{
"type": "WEB",
"url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
},
{
"type": "WEB",
"url": "https://www.debian.org/security/2021/dsa-5009"
},
{
"type": "WEB",
"url": "https://tomcat.apache.org/security-9.html"
},
{
"type": "WEB",
"url": "https://tomcat.apache.org/security-8.html"
},
{
"type": "WEB",
"url": "https://tomcat.apache.org/security-10.html"
},
{
"type": "WEB",
"url": "https://security.netapp.com/advisory/ntap-20211104-0001"
},
{
"type": "WEB",
"url": "https://security.gentoo.org/glsa/202208-34"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread.html/r83a35be60f06aca2065f188ee542b9099695d57ced2e70e0885f905c%40%3Cannounce.tomcat.apache.org%3E"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread.html/r8097a2d1550aa78e585fc77e602b9046e6d4099d8d132497c5387784@%3Ccommits.myfaces.apache.org%3E"
},
{
"type": "WEB",
"url": "https://kc.mcafee.com/corporate/index?page=content\u0026id=SB10379"
},
{
"type": "PACKAGE",
"url": "https://github.com/apache/tomcat"
}
],
"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": "Missing Release of Resource after Effective Lifetime in Apache Tomcat"
}
GHSA-WPRF-RGQF-H7J4
Vulnerability from github – Published: 2024-01-18 18:30 – Updated: 2024-01-18 18:30AVEVA PI Server versions 2023 and 2018 SP3 P05 and prior contain a vulnerability that could allow an unauthenticated user to cause the PI Message Subsystem of a PI Server to consume available memory resulting in throttled processing of new PI Data Archive events and a partial denial-of-service condition.
{
"affected": [],
"aliases": [
"CVE-2023-31274"
],
"database_specific": {
"cwe_ids": [
"CWE-772"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-01-18T18:15:08Z",
"severity": "MODERATE"
},
"details": "\nAVEVA PI Server versions 2023 and 2018 SP3 P05 and prior contain a vulnerability that could allow an unauthenticated user to cause the PI Message Subsystem of a PI Server to consume available memory resulting in throttled processing of new PI Data Archive events and a partial denial-of-service condition.\n\n\n\n\n",
"id": "GHSA-wprf-rgqf-h7j4",
"modified": "2024-01-18T18:30:25Z",
"published": "2024-01-18T18:30:25Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-31274"
},
{
"type": "WEB",
"url": "https://www.cisa.gov/news-events/ics-advisories/icsa-24-018-01"
}
],
"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"
}
]
}
GHSA-WQF3-H5G7-W9Q8
Vulnerability from github – Published: 2022-04-06 00:01 – Updated: 2022-04-15 00:01Racy interactions between dirty vram tracking and paging log dirty hypercalls Activation of log dirty mode done by XEN_DMOP_track_dirty_vram (was named HVMOP_track_dirty_vram before Xen 4.9) is racy with ongoing log dirty hypercalls. A suitably timed call to XEN_DMOP_track_dirty_vram can enable log dirty while another CPU is still in the process of tearing down the structures related to a previously enabled log dirty mode (XEN_DOMCTL_SHADOW_OP_OFF). This is due to lack of mutually exclusive locking between both operations and can lead to entries being added in already freed slots, resulting in a memory leak.
{
"affected": [],
"aliases": [
"CVE-2022-26356"
],
"database_specific": {
"cwe_ids": [
"CWE-667",
"CWE-772"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-04-05T13:15:00Z",
"severity": "MODERATE"
},
"details": "Racy interactions between dirty vram tracking and paging log dirty hypercalls Activation of log dirty mode done by XEN_DMOP_track_dirty_vram (was named HVMOP_track_dirty_vram before Xen 4.9) is racy with ongoing log dirty hypercalls. A suitably timed call to XEN_DMOP_track_dirty_vram can enable log dirty while another CPU is still in the process of tearing down the structures related to a previously enabled log dirty mode (XEN_DOMCTL_SHADOW_OP_OFF). This is due to lack of mutually exclusive locking between both operations and can lead to entries being added in already freed slots, resulting in a memory leak.",
"id": "GHSA-wqf3-h5g7-w9q8",
"modified": "2022-04-15T00:01:17Z",
"published": "2022-04-06T00:01:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-26356"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6ETPM2OVZZ6KOS2L7QO7SIW6XWT5OW3F"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UHFSRVLM2JUCPDC2KGB7ETPQYJLCGBLD"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/6ETPM2OVZZ6KOS2L7QO7SIW6XWT5OW3F"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UHFSRVLM2JUCPDC2KGB7ETPQYJLCGBLD"
},
{
"type": "WEB",
"url": "https://security.gentoo.org/glsa/202402-07"
},
{
"type": "WEB",
"url": "https://www.debian.org/security/2022/dsa-5117"
},
{
"type": "WEB",
"url": "https://xenbits.xenproject.org/xsa/advisory-397.txt"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2022/04/05/1"
},
{
"type": "WEB",
"url": "http://xenbits.xen.org/xsa/advisory-397.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-WR2R-8GRW-R4X2
Vulnerability from github – Published: 2026-07-14 21:32 – Updated: 2026-07-14 21:32A vulnerability was found in libsoup's HTTP/2 protocol implementation. The library fails to correctly release memory context blocks under specific stream termination conditions, such as when an HTTP/2 connection encounters window exhaustion or explicit stream resets. A remote, unauthenticated attacker acting as a malicious network peer can trick the connection engine into allocating stream states that are subsequently leaked during cleanup. Over a sustained period, this flaw allows the remote attacker to consume the system's heap allocations incrementally, triggering a denial of service (DoS) through an ultimate Out-of-Memory (OOM) application crash.
{
"affected": [],
"aliases": [
"CVE-2026-15713"
],
"database_specific": {
"cwe_ids": [
"CWE-772"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-14T20:16:57Z",
"severity": "MODERATE"
},
"details": "A vulnerability was found in libsoup\u0027s HTTP/2 protocol implementation. The library fails to correctly release memory context blocks under specific stream termination conditions, such as when an HTTP/2 connection encounters window exhaustion or explicit stream resets. A remote, unauthenticated attacker acting as a malicious network peer can trick the connection engine into allocating stream states that are subsequently leaked during cleanup. Over a sustained period, this flaw allows the remote attacker to consume the system\u0027s heap allocations incrementally, triggering a denial of service (DoS) through an ultimate Out-of-Memory (OOM) application crash.",
"id": "GHSA-wr2r-8grw-r4x2",
"modified": "2026-07-14T21:32:16Z",
"published": "2026-07-14T21:32:16Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-15713"
},
{
"type": "WEB",
"url": "https://access.redhat.com/security/cve/CVE-2026-15713"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2499941"
},
{
"type": "WEB",
"url": "https://gitlab.gnome.org/GNOME/libsoup/-/work_items/541"
}
],
"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-WRF7-4GW8-7MMQ
Vulnerability from github – Published: 2022-05-13 01:43 – Updated: 2025-04-20 03:46ImageMagick version 7.0.7-2 contains a memory leak in ReadYCBCRImage in coders/ycbcr.c.
{
"affected": [],
"aliases": [
"CVE-2017-15032"
],
"database_specific": {
"cwe_ids": [
"CWE-772"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2017-10-05T07:29:00Z",
"severity": "CRITICAL"
},
"details": "ImageMagick version 7.0.7-2 contains a memory leak in ReadYCBCRImage in coders/ycbcr.c.",
"id": "GHSA-wrf7-4gw8-7mmq",
"modified": "2025-04-20T03:46:20Z",
"published": "2022-05-13T01:43:37Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-15032"
},
{
"type": "WEB",
"url": "https://github.com/ImageMagick/ImageMagick/commit/241988ca28139ad970c1d9717c419f41e360ddb0"
},
{
"type": "WEB",
"url": "https://usn.ubuntu.com/3681-1"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-WV5M-7CHG-5VVV
Vulnerability from github – Published: 2022-05-13 01:14 – Updated: 2025-04-20 03:42ImageMagick 7.0.6-1 has a memory leak vulnerability in ReadDCMImage in coders\dcm.c.
{
"affected": [],
"aliases": [
"CVE-2017-12644"
],
"database_specific": {
"cwe_ids": [
"CWE-772"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2017-08-07T15:29:00Z",
"severity": "HIGH"
},
"details": "ImageMagick 7.0.6-1 has a memory leak vulnerability in ReadDCMImage in coders\\dcm.c.",
"id": "GHSA-wv5m-7chg-5vvv",
"modified": "2025-04-20T03:42:19Z",
"published": "2022-05-13T01:14:44Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-12644"
},
{
"type": "WEB",
"url": "https://github.com/ImageMagick/ImageMagick/issues/551"
},
{
"type": "WEB",
"url": "https://github.com/ImageMagick/ImageMagick/commit/a33f7498f9052b50e8fe8c8422a11ba84474cb42"
},
{
"type": "WEB",
"url": "https://usn.ubuntu.com/3681-1"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/100162"
}
],
"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-WV95-5HH8-J5CP
Vulnerability from github – Published: 2022-01-05 00:00 – Updated: 2022-01-12 00:01In Bluetooth, there is a possible application crash due to bluetooth flooding a device with LMP_AU_rand packet. This could lead to remote denial of service of bluetooth with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS06198608; Issue ID: ALPS06198608.
{
"affected": [],
"aliases": [
"CVE-2022-20023"
],
"database_specific": {
"cwe_ids": [
"CWE-772"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-01-04T16:15:00Z",
"severity": "MODERATE"
},
"details": "In Bluetooth, there is a possible application crash due to bluetooth flooding a device with LMP_AU_rand packet. This could lead to remote denial of service of bluetooth with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS06198608; Issue ID: ALPS06198608.",
"id": "GHSA-wv95-5hh8-j5cp",
"modified": "2022-01-12T00:01:32Z",
"published": "2022-01-05T00:00:57Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-20023"
},
{
"type": "WEB",
"url": "https://corp.mediatek.com/product-security-bulletin/January-2022"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-WX7V-5VJ2-RH4G
Vulnerability from github – Published: 2022-05-13 01:25 – Updated: 2025-04-20 03:42Memory leak in the CRYPTO_ASSOC function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (memory consumption).
{
"affected": [],
"aliases": [
"CVE-2015-7701"
],
"database_specific": {
"cwe_ids": [
"CWE-772"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2017-08-07T20:29:00Z",
"severity": "HIGH"
},
"details": "Memory leak in the CRYPTO_ASSOC function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (memory consumption).",
"id": "GHSA-wx7v-5vj2-rh4g",
"modified": "2025-04-20T03:42:20Z",
"published": "2022-05-13T01:25:43Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2015-7701"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=1274255"
},
{
"type": "WEB",
"url": "https://security.gentoo.org/glsa/201607-15"
},
{
"type": "WEB",
"url": "https://security.netapp.com/advisory/ntap-20171004-0001"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2016-0780.html"
},
{
"type": "WEB",
"url": "http://rhn.redhat.com/errata/RHSA-2016-2583.html"
},
{
"type": "WEB",
"url": "http://support.ntp.org/bin/view/Main/NtpBug2909"
},
{
"type": "WEB",
"url": "http://www.debian.org/security/2015/dsa-3388"
},
{
"type": "WEB",
"url": "http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/77281"
},
{
"type": "WEB",
"url": "http://www.securitytracker.com/id/1033951"
}
],
"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"
}
]
}
Mitigation MIT-3
Strategy: Language Selection
- Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- For example, languages such as Java, Ruby, and Lisp perform automatic garbage collection that releases memory for objects that have been deallocated.
Mitigation
It is good practice to be responsible for freeing all resources you allocate and to be consistent with how and where you free resources in a function. If you allocate resources that you intend to free upon completion of the function, you must be sure to free the resources at all exit points for that function including error conditions.
Mitigation MIT-47
Strategy: Resource Limitation
- Use resource-limiting settings provided by the operating system or environment. For example, when managing system resources in POSIX, setrlimit() can be used to set limits for certain types of resources, and getrlimit() can determine how many resources are available. However, these functions are not available on all operating systems.
- When the current levels get close to the maximum that is defined for the application (see CWE-770), then limit the allocation of further resources to privileged users; alternately, begin releasing resources for less-privileged users. While this mitigation may protect the system from attack, it will not necessarily stop attackers from adversely impacting other users.
- Ensure that the application performs the appropriate error checks and error handling in case resources become unavailable (CWE-703).
CAPEC-469: HTTP DoS
An attacker performs flooding at the HTTP level to bring down only a particular web application rather than anything listening on a TCP/IP connection. This denial of service attack requires substantially fewer packets to be sent which makes DoS harder to detect. This is an equivalent of SYN flood in HTTP. The idea is to keep the HTTP session alive indefinitely and then repeat that hundreds of times. This attack targets resource depletion weaknesses in web server software. The web server will wait to attacker's responses on the initiated HTTP sessions while the connection threads are being exhausted.