CVE-2017-17439

Published: Dec 6, 2017Updated: May 13, 2026 Sources: CVE List NVDCWE-476

7.5HIGH

NVD MITRE

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-476

Affected Products

debian

oss-project·GBaka debian gnu/linux

debian linuxOn-premOS

Operating Systems / linux-distro

heimdal project

commercialaka heimdal

heimdalOn-prem

Security Products / endpoint-av-edr

and 1 more affected products View all →

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Impact

Initial Access

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References

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

h5l.org

and 4 more references View all →

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