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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…
High7.5EPSS 3.4%
- Published
- Updated
- Reserved
- Assigned by
- mitre
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | High7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 3.4% · top 11% of all CVEs (3 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
Affected products
n/a
- affected n/a
References (7)
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=878144 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/heimdal/heimdal/commit/1a6a6e462dc2ac6111f9e02c6852ddec4849b887 (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://www.h5l.org/pipermail/heimdal-announce/2017-December/000008.html (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://www.h5l.org/pipermail/heimdal-discuss/2017-August/000259.html (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/heimdal/heimdal/issues/353 (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://h5l.org/advisories.html?show=2017-12-08 (opens in a new tab)x_refsource_CONFIRMx_transferred
- DSA-4055 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://trackcve.app/cve/CVE-2017-17439)Record last updated .