CVE-2017-17439

NONE EPSS 87.5%

Published Dec 6, 20178y ago · Modified Jun 17, 20262w ago

Published Dec 6, 2017 8y ago

Last Modified Jun 17, 2026 2w ago

Description

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.

Threat Intelligence

EPSS Exploit Probability

87.5% percentile

Exploit & Patch Status

No Known Exploit

Patch Available

Weaknesses 1

CWE-476 NULL Pointer Dereference Memory Safety

Affected Products 2

Vendor	Product	Version	Range
debian	debian_linux	9.0	any
heimdal_project	heimdal	*	≤7.4.0

References 7

h5l.org http://h5l.org/advisories.html?show=2017-12-08
h5l.org http://www.h5l.org/pipermail/heimdal-announce/2017-December/000008.html
h5l.org http://www.h5l.org/pipermail/heimdal-discuss/2017-August/000259.html

Third Party Advisory
bugs.debian.org https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=878144

Issue TrackingMailing ListThird Party Advisory
github.com https://github.com/heimdal/heimdal/commit/1a6a6e462dc2ac6111f9e02c6852ddec4849b887

Third Party Advisory
github.com https://github.com/heimdal/heimdal/issues/353

PatchThird Party Advisory
debian.org https://www.debian.org/security/2017/dsa-4055

Third Party Advisory

Remediation

github.com https://github.com/heimdal/heimdal/issues/353

PatchThird Party Advisory