High severity · published Jul 22, 2022
CVE-2022-34037
An out-of-bounds read in the rewrite function at /modules/caddyhttp/rewrite/rewrite.go in Caddy v2.5.1 allows attackers to cause a Denial of Service (DoS) via a crafted URI
7.5
CVSS
1.2%
EPSS
No
On KEV
Description
An out-of-bounds read in the rewrite function at /modules/caddyhttp/rewrite/rewrite.go in Caddy v2.5.1 allows attackers to cause a Denial of Service (DoS) via a crafted URI. Note: This has been disputed as a bug, not a security vulnerability, in the Caddy web server that emerged when an administrator's bad configuration containing a malformed request URI caused the server to return an empty reply instead of a valid HTTP response to the client.
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)1.2% · higher than 68% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CA
Caddy · Caddyserver
2.5.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2022-34037
CVE.org
https://www.cve.org/CVERecord?id=CVE-2022-34037
Exploit
https://github.com/caddyserver/caddy/issues/4775
github.com
https://github.com/caddyserver/caddy/issues/4775#issuecomment-1203388116
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