CVE-2017-17439 Null dereference in n/a

What is CVE-2017-17439?

CVE-2017-17439 is a high-severity vulnerability in Debian Debian Linux, published on 6 Dec 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-476

Which versions are affected by CVE-2017-17439?

It affects 2 products.

Products include Debian Debian Linux, Heimdal Project Heimdal.

How do I fix CVE-2017-17439?

Apply the vendor's patch.

Is CVE-2017-17439 being exploited?

There is no known exploitation of CVE-2017-17439 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2017-17439, CLEANSTART-2024-ZN45970, DEBIAN-CVE-2017-17439, DSA-4055-1, GHSA-gc5p-r2vh-qc88, MGASA-2017-0485.