NULL Pointer Dereference Affecting heimdal/heimdal package, versions [,7.5.0)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
3.43% (89th percentile)

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  • Snyk IDSNYK-UNMANAGED-HEIMDALHEIMDAL-2364877
  • published26 Jan 2022
  • disclosed6 Dec 2017
  • creditUnknown

Introduced: 6 Dec 2017

CVE-2017-17439  (opens in a new tab)
CWE-476  (opens in a new tab)

How to fix?

Upgrade heimdal/heimdal to version 7.5.0 or higher.

Overview

Affected versions of this package are vulnerable to NULL Pointer Dereference. 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.

CVSS Base Scores

version 3.1