High severity · published Jul 10, 2025
CVE-2025-49630
In certain proxy configurations, a denial of service attack against Apache HTTP Server versions 2.4.26 through to 2.4.63 can be triggered by untrusted clients causing an assertion…
7.5
CVSS
1.4%
EPSS
No
On KEV
Description
In certain proxy configurations, a denial of service attack against Apache HTTP Server versions 2.4.26 through to 2.4.63 can be triggered by untrusted clients causing an assertion in mod_proxy_http2.
Configurations affected are a reverse proxy is configured for an HTTP/2 backend, with ProxyPreserveHost set to "on".
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.4% · higher than 71% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HS
HTTP Server · Apache
2.4.26 before 2.4.64 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-49630
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-49630
Vendor Advisory
https://httpd.apache.org/security/vulnerabilities_24.html
www.openwall.com
http://www.openwall.com/lists/oss-security/2025/07/10/2
www.openwall.com
http://www.openwall.com/lists/oss-security/2025/07/10/7
lists.debian.org
https://lists.debian.org/debian-lts-announce/2025/08/msg00009.html
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