CVE-2017-7657

In Eclipse Jetty, versions 9.2.x and older, 9.3.x (all configurations), and 9.4.x (non-default configuration with RFC2616 compliance enabled), transfer-encoding chunks are handled poorly. The chunk length parsing was vulnerable to an integer overflow. Thus a large chunk size could be interpreted as a smaller chunk size and content sent as chunk body could be interpreted as a pipelined request. If Jetty was deployed behind an intermediary that imposed some authorization and that intermediary allowed arbitrarily large chunks to be passed on unchanged, then this flaw could be used to bypass the authorization imposed by the intermediary as the fake pipelined request would not be interpreted by the intermediary as a request.

Weakness

The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control.

Affected Software

Name	Vendor	Start Version	End Version
Jetty	Eclipse	*	9.2.26 (including)
Jetty	Eclipse	9.3.0 (including)	9.3.24 (excluding)
Jetty	Eclipse	9.4.0 (including)	9.4.11 (excluding)
Red Hat Data Grid 7.3.7	RedHat		*
Red Hat Fuse 7.3	RedHat	jetty	*
Jetty8	Ubuntu	esm-apps/xenial	*
Jetty8	Ubuntu	esm-infra-legacy/trusty	*
Jetty8	Ubuntu	trusty	*
Jetty8	Ubuntu	trusty/esm	*
Jetty8	Ubuntu	upstream	*
Jetty8	Ubuntu	xenial	*
Jetty9	Ubuntu	artful	*
Jetty9	Ubuntu	bionic	*
Jetty9	Ubuntu	esm-apps/bionic	*
Jetty9	Ubuntu	esm-apps/xenial	*
Jetty9	Ubuntu	upstream	*
Jetty9	Ubuntu	xenial	*

Potential Mitigations

Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
If possible, choose a language or compiler that performs automatic bounds checking.
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Use libraries or frameworks that make it easier to handle numbers without unexpected consequences.
Examples include safe integer handling packages such as SafeInt (C++) or IntegerLib (C or C++). [REF-106]
Perform input validation on any numeric input by ensuring that it is within the expected range. Enforce that the input meets both the minimum and maximum requirements for the expected range.
Use unsigned integers where possible. This makes it easier to perform validation for integer overflows. When signed integers are required, ensure that the range check includes minimum values as well as maximum values.
Understand the programming language’s underlying representation and how it interacts with numeric calculation (CWE-681). Pay close attention to byte size discrepancies, precision, signed/unsigned distinctions, truncation, conversion and casting between types, “not-a-number” calculations, and how the language handles numbers that are too large or too small for its underlying representation. [REF-7]
Also be careful to account for 32-bit, 64-bit, and other potential differences that may affect the numeric representation.

https://cwe.mitre.org/data/definitions/92.html

NVD	https://nvd.nist.gov/vuln/detail/CVE-2017-7657
CWE	https://cwe.mitre.org/data/definitions/190.html

Integer Overflow or Wraparound

Weakness

Affected Software

Potential Mitigations

References

CVE-2017-7657

Integer Overflow or Wraparound

Weakness

Affected Software

Potential Mitigations

Related Attack Patterns

References