HighFix available
apache2 — security advisory
An attacker, opening a HTTP/2 connection with an initial window size of 0, was able to block handling of that connection indefinitely in Apache HTTP Server. This could be used to exhaust worker resources in the server, similar to the well known "slow loris" attack pattern. This has been fixed in version 2.4.58, so that such connection are terminated properly after the configured connection timeout. This issue affects Apache HTTP Server: from 2.4.55 through 2.4.57. Users are recommended to upgrade to version 2.4.58, which fixes the issue.
- Products
- apache2
- Affected versions
- Not specified
- Fixed versions
- 2.4.58-r0
- CVEs
- CVE-2023-43622
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 15:00 UTC · Revision 1
Source evidence
An attacker, opening a HTTP/2 connection with an initial window size of 0, was able to block handling of that connection indefinitely in Apache HTTP Server. This could be used to exhaust worker resources in the server, similar to the well known "slow loris" attack pattern. This has been fixed in version 2.4.58, so that such connection are terminated properly after the configured connection timeout. This issue affects Apache HTTP Server: from 2.4.55 through 2.4.57. Users are recommended to upgrade to version 2.4.58, which fixes the issue.
osv:ALPINE-CVE-2023-43622
apache2
Fixed versions: 2.4.58-r0
apache2
Fixed versions: 2.4.58-r0
apache2
Fixed versions: 2.4.58-r0
apache2
Fixed versions: 2.4.58-r0
apache2
Fixed versions: 2.4.58-r0
apache2
Fixed versions: 2.4.58-r0
apache2
Fixed versions: 2.4.58-r0
apache2
Fixed versions: 2.4.58-r0
apache2
Fixed versions: 2.4.58-r0
apache2
Fixed versions: 2.4.58-r0
Complete source record
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"modified": "2026-10-26T17:17:58.643129164Z",
"provider": "osv",
"upstream": [
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"references": [
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"source_id": "core-osv",
"document_id": 454503,
"published_at": "2023-10-23T07:15:11.243+00:00"
}