CVE-2018-20217: debian debian_linux Reachable Assertion
CVSS: 5.3v3.1MediumModified
AliasesALPINE-CVE-2018-20217MGASA-2019-0028SUSE-SU-2019:0111-1SUSE-SU-2019:0113-1SUSE-SU-2019:0113-2RHBA-2019:2599UBUNTU-CVE-2018-20217DEBIAN-CVE-2018-20217openSUSE-SU-2019:0063-1
Published 26-12-2018Last modified 05-08-2024
Vulnerability summary
CVE-2018-20217 is a medium (CVSS 5.3) Reachable Assertion vulnerability in debian debian_linux. EPSS estimates a 1.42% chance of exploitation in the next 30 days, higher than 72.3% of scored vulnerabilities.
CVSS score
5.3/10
010
Medium · v3.1 (NVD)EPSS score
1.42%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 4 · Related 2Timeline
- 26-12-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
A Reachable Assertion issue was discovered in the KDC in MIT Kerberos 5 (aka krb5) before 1.17. If an attacker can obtain a krbtgt ticket using an older encryption type (single-DES, triple-DES, or RC4), the attacker can crash the KDC by making an S4U2Self request.
CVSS metrics
7 scores · 5 sources · 3 versionsMedium 5.3Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:HSourcesAll 4 agree
- OSV · AlpineEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Medium 5.3Preferred score · OSV · Red hat (Ecosystem advisory) · calculated from vector
CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:HSourcesAll 2 agree
- OSV · UbuntuEcosystem advisory · calculated5.3MediumCVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Low 3.5Preferred score · NVD (NIST)
AV:N/AC:M/Au:S/C:N/I:N/A:PSourcesSingle source
EPSS trend
Probability
1.42%
Chance of exploitation in the next 30 days
Percentile
72%
Versus all other CVEs
30-day change
0.00 pp
From 1.42% on 19-09-2026
19-09-202619-10-2026
EPSS score1.42%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Suse16 products
- krb5&distro=SUSE Enterprise Storage 4< 1.12.5-40.31.1
- krb5&distro=SUSE Linux Enterprise Desktop 12 SP3< 1.12.5-40.31.1
- krb5&distro=SUSE Linux Enterprise Desktop 12 SP4< 1.12.5-40.31.1
- krb5&distro=SUSE Linux Enterprise Server 12 SP1-LTSS< 1.12.1-38.13.2
- krb5&distro=SUSE Linux Enterprise Server 12 SP2-BCL< 1.12.5-40.31.1
Redhat9 products
- krb5< 0:1.15.1-37.el7_7.2
- krb5-debuginfo< 0:1.15.1-37.el7_7.2
- krb5-devel< 0:1.15.1-37.el7_7.2
- krb5-libs< 0:1.15.1-37.el7_7.2
- krb5-pkinit< 0:1.15.1-37.el7_7.2
Debian2 products
- krb5< 1.16.2-1
- debian_linuxEOL8.0 | 9.0
Opensuse2 products
- krb5-mini&distro=openSUSE Leap 15.0< 1.15.2-lp150.5.3.1
- krb5&distro=openSUSE Leap 15.0< 1.15.2-lp150.5.3.1
Alpine1 product
- krb5< 1.15.4-r0 | < 1.14.3-r3
Mageia1 product
- krb5< 1.15.1-2.4.mga6
Mit1 product
- kerberos< 5-1.17
Ubuntu1 product
- krb5< 1.12+dfsg-2ubuntu5.4+esm1 | < 1.13.2+dfsg-5ubuntu2.2+esm3 | < 1.16-2ubuntu0.3
8 vendors · 33 products
References
26 links- github.com/krb5/krb5/commit/5e6d1796106df8ba6bc1973ee0917c170d929086X Refsource CONFIRMPatchThird Party Advisory
lists.debian.org/debian-lts-announce/2019/01/msg00020.htmlMailing ListX Refsource MLISTThird Party Advisory- lists.debian.org/debian-lts-announce/2021/09/msg00019.htmlMailing ListX Refsource MLISTThird Party Advisory
Show all 26 references
- lists.opensuse.org/archives/…Advisory