CVE-2017-17439
mediumpriority · track · 31EPSS 0.034 · 89 %ileEUUSEPSS · scored 2026-10-28
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
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affected products (3)
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also known as (3)
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sources
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references (17)
External citations — patches, advisories, analysis.
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=878144cnnvd
- https://github.com/heimdal/heimdal/commit/1a6a6e462dc2ac6111f9e02c6852ddec4849b887cnnvd
- https://github.com/heimdal/heimdal/issues/353cnnvd
- http://h5l.org/advisories.html?show=2017-12-08enisa_euvd
- http://www.h5l.org/pipermail/heimdal-announce/2017-December/000008.htmlenisa_euvd
- http://www.h5l.org/pipermail/heimdal-discuss/2017-August/000259.htmlenisa_euvd
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=878144enisa_euvd
- https://github.com/heimdal/heimdal/commit/1a6a6e462dc2ac6111f9e02c6852ddec4849b887enisa_euvd
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