Bug 1776860 (CVE-2019-14842) - CVE-2019-14842 libnbd: remote code execution vulnerability
Summary: CVE-2019-14842 libnbd: remote code execution vulnerability
Keywords:
Status: CLOSED UPSTREAM
Alias: CVE-2019-14842
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 1776862
Blocks:
TreeView+ depends on / blocked
 
Reported: 2019-11-26 14:01 UTC by Dhananjay Arunesh
Modified: 2019-12-06 00:14 UTC (History)
1 user (show)

Fixed In Version: libnbd 1.0.3
Doc Type: If docs needed, set a value
Doc Text:
A bounds check vulnerability was found in libnbd's structured reply feature where the check was supposed to test for chunk offsets smaller than the beginning of the request but did not work because of signed/unsigned confusion. Structured reply is a feature of the newstyle NBD protocol allowing the server to send a reply in chunks. If one of these chunks contains a negative offset, then data under control of the server is written to memory before the read buffer supplied by the client. If the read buffer is located on the stack then this allows the stack, the return address from nbd_pread() to be trivially modified, allowing arbitrary code execution under the control of the server. If the buffer is located on the heap then other memory objects before the buffer can be overwritten, which again would usually lead to arbitrary code execution.
Clone Of:
Environment:
Last Closed: 2019-11-26 19:04:58 UTC


Attachments (Terms of Use)

Description Dhananjay Arunesh 2019-11-26 14:01:57 UTC
A vulnerabilty was found in libnbd. There is an improper bounds checking, when receiving a structured reply some offset/lengths sent by the server could cause libnbd to execute arbitrary code under control of a malicious server.

Comment 1 Dhananjay Arunesh 2019-11-26 14:03:38 UTC
Created libnbd tracking bugs for this issue:

Affects: fedora-all [bug 1776862]

Comment 2 Dhananjay Arunesh 2019-11-26 14:06:51 UTC
External References:

https://www.redhat.com/archives/libguestfs/2019-October/msg00060.html

Comment 3 Product Security DevOps Team 2019-11-26 19:04:58 UTC
This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.

Comment 4 Eric Christensen 2019-12-06 00:14:07 UTC
Statement:

This vulnerability does not affect any package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.


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