CVE intelligence and bounded remediation
CVE-2017-17439 — Debian Debian Linux security vulnerability
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.
- Severity
- High
- CVSS
- 7.5 (3.0)
- Published
- 2017-12-06
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-476
Affected products
- debian / debian_linux / 9.0
- heimdal_project / heimdal
Matched remediation archetype
Buffer bounds, memory safety, and memory corruption
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Check exposure
- Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
- Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
- Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.
Remediate safely
- Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
- Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
- Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.
Authoritative sources
Complete CVE record and remediation plan
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