Where
-Infinity
0
Severity
9.8
AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L

Use of Out-of-range Pointer Offset vulnerability in Cesanta Mongoose Web Server v7.14 allows to write a NULL byte value beyond the memory space dedicated for the hostname field.

Remedy

It is suggested to update the Mongoose Web Server library to v7.15.
First published (updated )
Severity
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Cesanta mjs v2.20.0 was discovered to contain a function pointer hijacking vulnerability via the function mjsgetptr(). This vulnerability allows attackers to execute arbitrary code via a crafted input.

First published (updated )
Severity
9.8
Buffer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

DISPUTED A buffer overflow vulnerability exists in the mggethttpheader function in Cesanta Mongoose 6.18 due to a lack of bounds checking. A crafted HTTP header can exploit this bug. NOTE: a committer has stated "this will not happen in practice."

1 / 2
First published (updated )
Severity
9.8
Use After Free
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An invalid read of 8 bytes due to a use-after-free vulnerability during a "return" in the mghttpgetprotodata function in mongoose.c in Cesanta Mongoose Embedded Web Server Library 6.13 and earlier allows a denial of service (application crash) or remote code execution.

First published (updated )
Severity
9.8
Use After Free
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An invalid read of 8 bytes due to a use-after-free vulnerability during a "NULL test" in the mghttpgetprotodata function in mongoose.c in Cesanta Mongoose Embedded Web Server Library 6.13 and earlier allows a denial of service (application crash) or remote code execution.

First published (updated )
Severity
9.8
Use After Free
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An invalid read of 8 bytes due to a use-after-free vulnerability in the mghttpfreeprotodatacgi function call in mongoose.c in Cesanta Mongoose Embedded Web Server Library 6.13 and earlier allows a denial of service (application crash) or remote code execution.

First published (updated )
Severity
9.8
Use After Free
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An invalid write of 8 bytes due to a use-after-free vulnerability in the mghttpfreeprotodatacgi function call in mongoose.c in Cesanta Mongoose Embedded Web Server Library 6.13 and earlier allows a denial of service (application crash) or remote code execution.

First published (updated )
Severity
9.8
Integer Overflow, Buffer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An exploitable memory corruption vulnerability exists in the Websocket protocol implementation of Cesanta Mongoose 6.8. A specially crafted websocket packet can cause an integer overflow, leading to a heap buffer overflow and resulting in denial of service and potential remote code execution. An attacker needs to send a specially crafted websocket packet over network to trigger this vulnerability.

First published (updated )
Severity
9.8
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An exploitable arbitrary memory read vulnerability exists in the MQTT packet parsing functionality of Cesanta Mongoose 6.8. A specially crafted MQTT packet can cause an arbitrary out-of-bounds memory read and write potentially resulting in information disclosure, denial of service and remote code execution. An attacker needs to send a specially crafted MQTT packet over the network to trigger this vulnerability.

First published (updated )
Severity
9.8
Use After Free
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An exploitable use-after-free vulnerability exists in the HTTP server implementation of Cesanta Mongoose 6.8. An ordinary HTTP POST request with a CGI target can cause a reuse of previously freed pointer potentially resulting in remote code execution. An attacker needs to send this HTTP request over the network to trigger this vulnerability.

First published (updated )
Severity
9.8
Buffer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An exploitable stack buffer overflow vulnerability exists in the MQTT packet parsing functionality of Cesanta Mongoose 6.8. A specially crafted MQTT SUBSCRIBE packet can cause a stack buffer overflow resulting in remote code execution. An attacker needs to send a specially crafted MQTT packet over the network to trigger this vulnerability.

First published (updated )
Severity
9.8
Use After Free
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An exploitable memory corruption vulnerability exists in the Websocket protocol implementation of Cesanta Mongoose 6.8. A specially crafted websocket packet can cause a buffer to be allocated while leaving stale pointers which leads to a use-after-free vulnerability which can be exploited to achieve remote code execution. An attacker needs to send a specially crafted websocket packet over the network to trigger this vulnerability.

First published (updated )
Severity
9.8
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An integer overflow in parsemqtt in mongoose.c in Cesanta Mongoose 6.16 allows an attacker to achieve remote DoS (infinite loop), or possibly cause an out-of-bounds write, by sending a crafted MQTT protocol packet.

First published (updated )
Severity
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

This affects the package cesanta/mongoose before 7.6. The unsafe handling of file names during upload using mghttpupload() method may enable attackers to write files to arbitrary locations outside the designated target folder.

First published (updated )
Severity
9.8
Buffer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

DISPUTED In mjsjson.c in Cesanta MongooseOS mJS 1.26, a maliciously formed JSON string can trigger an off-by-one heap-based buffer overflow in mjsjsonparse, which can potentially lead to redirection of control flow. NOTE: the original reporter disputes the significance of this finding because "there isn’t very much of an opportunity to exploit this reliably for an information leak, so there isn’t any real security impact."

1 / 2
First published (updated )
Severity
9.8
Buffer Overflow
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An issue was discovered in Mongoose before 6.15. The parsemqtt() function in mgmqtt.c has a critical heap-based buffer overflow.

First published (updated )
Severity
9.8
Integer Overflow, Code Injection
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Cesanta Software Mongoose-OS v2.17.0 is vulnerable to integer wrap-around in function mmmalloc. This improper memory assignment can lead to arbitrary memory allocation, resulting in unexpected behavior such as a crash or a remote code injection/execution.

Remedy

Cesanta Software Mongoose update available
First published (updated )
Severity
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Cesanta MJS 2.20.0 has a getpropbuiltinforeign out-of-bounds read if a Built-in API name occurs in a substring of an input string.

First published (updated )
Severity
9.3
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Mongoose is an embedded web server and network library. Prior to 7.23, a network attacker can impersonate a TLS server to a Mongoose client configured with a multi-certificate CA bundle. In src/tlsbuiltin.c, the mgtlsinit() function stores the bundle in tls->cabundleder while tls->cader.len remains zero, and mgtlsrecvcert() uses tlsbundlefind() to accept a Common Name match without calling mgtlsverifycertsignature(). A forged self-signed certificate can therefore satisfy hostname and CertificateVerify checks and enable interception, credential disclosure, traffic modification, and malicious responses. This issue is fixed in version 7.23.

First published (updated )
Severity
9.1
AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Mongoose is an embedded web server and network library. Prior to version 7.22, an on-path network attacker with a wildcard certificate for a parent domain can impersonate deeper subdomains to a client using the built-in TLS stack. The mgtlsverifycertsan() and mgtlsverifycertcn() functions in src/tlsbuiltin.c call mgmatch(), whose wildcard can cross DNS label boundaries, so a pattern such as .example.com can match foo.bar.example.com. The resulting hostname verification bypass permits interception and modification of TLS traffic. This issue is fixed in version 7.22.

First published (updated )
Severity
9.1
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Mongoose is an embedded web server and network library. Priro to version 7.22, a remote unauthenticated attacker can send an HTTP request containing both Content-Length and Transfer-Encoding: chunked. The clcount and tecount checks in the mghttpparse() and httpcb() paths in src/http.c accept both headers and prioritize chunked encoding, while a Content-Length-preferring reverse proxy can use a different request boundary. This CL.TE desynchronization can inject requests that access or modify resources in another user context. This issue is fixed in version 7.22.

First published (updated )
Severity
9.1
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Mongoose is an embedded web server and network library. Prior to 7.22, a remote unauthenticated attacker can exploit an HTTP/1.0 reverse-proxy deployment by sending a request with Transfer-Encoding: chunked and conflicting framing. The httpcb() function in src/http.c tests hm.proto.len with an impossible greater-than-eight condition even though mghttpparse() requires an eight-byte protocol string, so ishttp10 is never set. Mongoose consequently processes chunked encoding that an HTTP/1.0 proxy can ignore, enabling request smuggling and unauthorized access or state changes. This issue is fixed in version 7.22.

First published (updated )
Severity
9.1
AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

Mongoose is an embedded web server and network library. Prior to version 7.22, an on-path network attacker with a wildcard certificate for a parent domain can impersonate deeper subdomains to a client using the built-in TLS stack. The mgtlsverifycertsan() and mgtlsverifycertcn() functions in src/tlsbuiltin.c call mgmatch(), whose wildcard can cross DNS label boundaries, so a pattern such as .example.com can match foo.bar.example.com. The resulting hostname verification bypass permits interception and modification of TLS traffic. This issue is fixed in version 7.22.

First published (updated )
Severity
9.1
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Mongoose is an embedded web server and network library. Priro to version 7.22, a remote unauthenticated attacker can send an HTTP request containing both Content-Length and Transfer-Encoding: chunked. The clcount and tecount checks in the mghttpparse() and httpcb() paths in src/http.c accept both headers and prioritize chunked encoding, while a Content-Length-preferring reverse proxy can use a different request boundary. This CL.TE desynchronization can inject requests that access or modify resources in another user context. This issue is fixed in version 7.22.

First published (updated )
Severity
9.1
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Mongoose is an embedded web server and network library. Prior to 7.22, a remote unauthenticated attacker can exploit an HTTP/1.0 reverse-proxy deployment by sending a request with Transfer-Encoding: chunked and conflicting framing. The httpcb() function in src/http.c tests hm.proto.len with an impossible greater-than-eight condition even though mghttpparse() requires an eight-byte protocol string, so ishttp10 is never set. Mongoose consequently processes chunked encoding that an HTTP/1.0 proxy can ignore, enabling request smuggling and unauthorized access or state changes. This issue is fixed in version 7.22.

First published (updated )
Severity
9.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

The mgtlsinit function in Cesanta Mongoose HTTPS server 7.0 (compiled with OpenSSL support) is vulnerable to remote OOB write attack via connection request after exhausting memory pool.

First published (updated )
Severity
9.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

The mgtlsinit function in Cesanta Mongoose HTTPS server 7.0 and 6.7-6.18 (compiled with mbedTLS support) is vulnerable to remote OOB write attack via connection request after exhausting memory pool.

First published (updated )
Severity
9.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

The mghttpservefile function in Cesanta Mongoose HTTP server 7.0 is vulnerable to remote OOB write attack via connection request after exhausting memory pool.

First published (updated )
Severity
9.1
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

An exploitable arbitrary memory read vulnerability exists in the MQTT packet-parsing functionality of Cesanta Mongoose 6.13. It is a heap-based buffer over-read in a parsemqtt getu16 call. A specially crafted MQTT SUBSCRIBE packet can cause an arbitrary out-of-bounds memory read potentially resulting in information disclosure and denial of service. An attacker needs to send a specially crafted MQTT packet over the network to trigger this vulnerability.

First published (updated )
Severity
9.1
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

An exploitable arbitrary memory read vulnerability exists in the MQTT packet-parsing functionality of Cesanta Mongoose 6.13. It is a heap-based buffer over-read in mgmqttnextsubscribetopic. A specially crafted MQTT SUBSCRIBE packet can cause an arbitrary out-of-bounds memory read potentially resulting in information disclosure and denial of service. An attacker needs to send a specially crafted MQTT packet over the network to trigger this vulnerability.

First published (updated )

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