CVE-2017-17439
heimdal - security update
7.5
HIGH
CVSS 3.1
EPSS 3.8%
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.
How to fix CVE-2017-17439
To remediate CVE-2017-17439, upgrade the affected package to a fixed version below.
- —upgrade to 7.4.0-r2 or later
- —upgrade to 7.5.0+dfsg-1 or later
- —upgrade to 7.1.0+dfsg-13+deb9u2 or later
Is CVE-2017-17439 being exploited?
Low — EPSS is 3.8%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0, < 7.4.0-r2
- from 0, < 7.5.0+dfsg-1
- from 0, < 7.1.0+dfsg-13+deb9u2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |