CVE-2019-14842
highpriority · track · 40EPSS 0.018 · 79 %ileEUUSEPSS · scored 2026-10-27
Structured reply is a feature of the newstyle NBD protocol allowing the server to send a reply in chunks. A bounds check which was supposed to test for chunk offsets smaller than the beginning of the request did not work because of signed/unsigned confusion. 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 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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.3–9.8
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
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references (8)
External citations — patches, advisories, analysis.
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14842cnnvd
- https://github.com/libguestfs/libnbdPatchcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2019-14842cnnvd
- https://www.redhat.com/archives/libguestfs/2019-October/msg00060.htmlcnnvd
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14842enisa_euvd
- https://www.redhat.com/archives/libguestfs/2019-October/msg00060.htmlenisa_euvd
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14842Issue TrackingThird Party Advisorynvd
- https://www.redhat.com/archives/libguestfs/2019-October/msg00060.htmlPatchThird Party Advisorynvd
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