vulnwire
7.5high

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 fi…

Published 8 y ago · modified 4 mo ago · JSON

CVSS
7.5
v3.0 · NVD
CISA KEV
No
not known exploited
EPSS
3.4%
percentile 89%
Public exploits
0
none known

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.

Exploit prediction (EPSS)

3.43% probability of exploitation in the next 30 days, higher than 89% of all scored CVEs.

CVSS scores

Assigned byVersionScoreVector
NVD3.07.5CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD2.05.0AV:N/AC:L/Au:N/C:N/I:N/A:P

Classification

Weakness

References

  • bugs.debian.org /cgi-bin/bugreport.cgi?bug=878144 · x_refsource_CONFIRM, x_transferred
  • github.com /heimdal/heimdal/commit/1a6a6e462dc2ac6111f9e02c6852ddec4849b887 · x_refsource_CONFIRM, x_transferred
  • h5l.org /pipermail/heimdal-announce/2017-December/000008.html · x_refsource_CONFIRM, x_transferred
  • h5l.org /pipermail/heimdal-discuss/2017-August/000259.html · x_refsource_MISC, x_transferred
  • github.com /heimdal/heimdal/issues/353 · x_refsource_CONFIRM, x_transferred
  • h5l.org /advisories.html?show=2017-12-08 · x_refsource_CONFIRM, x_transferred
  • debian.org /security/2017/dsa-4055 · vendor-advisory, x_refsource_DEBIAN, x_transferred

Sources

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