CVE-2017-17439: In Heimdal through 7.4, remote unauthenticated attackers are able to crash the KDC by sending a crafted UDP packet containing empty data fields for client name…

PriorityP343high7.5CVSS 3.0

AVNACLPRNUINSUCNINAH

EPSS

3.43%

87.6th percentile

In Heimdal through 7.4, remote unauthenticated attackers are able to crash the KDC by sending a crafted UDP packet containing empty data fields for client name or realm. The parser would unconditionally dereference NULL pointers in that case, leading to a segmentation fault. This is related to the _kdc_as_rep function in kdc/kerberos5.c and the der_length_visible_string function in lib/asn1/der_length.c.

Affected

7 ranges

Vendor	Product	Version range	Fixed in
debian	debian_linux	—	—
debian	heimdal	< heimdal 7.5.0+dfsg-1 (bookworm)	heimdal 7.5.0+dfsg-1 (bookworm)
heimdal_project	heimdal	<= 7.4.0	—
heimdal_project	heimdal	>= 0 < 7.5.0+dfsg-1	7.5.0+dfsg-1
heimdal_project	heimdal	>= 0 < 7.5.0+dfsg-1	7.5.0+dfsg-1
heimdal_project	heimdal	>= 0 < 7.5.0+dfsg-1	7.5.0+dfsg-1
heimdal_project	heimdal	>= 0 < 7.5.0+dfsg-1	7.5.0+dfsg-1

CVSS provenance

nvdv3.07.5HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P

osv7.5HIGH

vendor_debian7.5HIGH

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