High severity · published Jun 23, 2023
CVE-2023-34188
The HTTP server in Mongoose before 7.10 accepts requests containing negative Content-Length headers
7.5
CVSS
1%
EPSS
No
On KEV
Description
The HTTP server in Mongoose before 7.10 accepts requests containing negative Content-Length headers. By sending a single attack payload over TCP, an attacker can cause an infinite loop in which the server continuously reparses that payload, and does not respond to any other requests.
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)1.0% · higher than 63% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
Mongoose · Cesanta
before 7.10 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-34188
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-34188
blog.narfindustries.com
https://blog.narfindustries.com/blog/narf-discovers-critical-vulnerabilities-in-cesanta-mongoose-http-server
Patch
https://github.com/cesanta/mongoose/commit/4663090a8fb036146dfe77718cff612b0101cb0f
Release Notes
https://github.com/cesanta/mongoose/compare/7.9...7.10
Patch
https://github.com/cesanta/mongoose/pull/2197
security.netapp.com
https://security.netapp.com/advisory/ntap-20250228-0001/
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