CVE-2015-7871: debian debian_linux Improper Authentication
CVSS: 9.8v3.1CriticalModified
AliasesUBUNTU-CVE-2015-7871DEBIAN-CVE-2015-7871
Published 07-08-2017Last modified 06-08-2024
Vulnerability summary
CVE-2015-7871 is a critical (CVSS 9.8) Improper Authentication vulnerability in debian debian_linux. EPSS estimates a 81.76% chance of exploitation in the next 30 days, higher than 99.6% of scored vulnerabilities. 1 public exploit is recorded.
CVSS score
9.8/10
010
Critical · v3.1 (NVD)EPSS score
81.76%
0%100%
Critical · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1metasploit
Advisory lineage
Upstream 0 · Downstream 8 · Related 5Timeline
- 07-08-2017PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
Description
Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass authentication.
CVSS metrics
5 scores · 3 sources · 3 versionsCritical 9.8Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Critical 9.8Preferred score · OSV · Ubuntu (Ecosystem advisory) · calculated from vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSourcesSingle source
High 7.5Preferred score · NVD (NIST)
AV:N/AC:L/Au:N/C:P/I:P/A:PSourcesSingle source
EPSS trend
Probability
81.76%
Chance of exploitation in the next 30 days
Percentile
100%
Versus all other CVEs
30-day change
0.00 pp
From 81.76% on 18-09-2026
18-09-202618-10-2026
EPSS score81.76%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundNTP "NAK to the Future"
auxiliary/scanner/ntp/ntp_nak_to_the_future
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Netapp5 products
Debian2 products
- ntp< 1:4.2.8p4+dfsg-1
- debian_linuxEOL7.0 | 8.0 | 9.0
Ntp1 product
- ntp≥ 4.2.6, < 4.2.8 | ≥ 4.3.0, < 4.3.77 | 4.2.5:p186 | 4.2.5:p187 | 4.2.5:p188 | 4.2.5:p189 | 4.2.5:p190 | 4.2.5:p191 | 4.2.5:p192 | 4.2.5:p193 | 4.2.5:p194 | 4.2.5:p195 | 4.2.5:p196 | 4.2.5:p197 | 4.2.5:p198 | 4.2.5:p199 | 4.2.5:p200 | 4.2.5:p201 | 4.2.5:p202 | 4.2.5:p203 | 4.2.5:p204 | 4.2.5:p205 | 4.2.5:p206 | 4.2.5:p207 | 4.2.5:p208 | 4.2.5:p209 | 4.2.5:p210 | 4.2.5:p211 | 4.2.5:p212 | 4.2.5:p213 | 4.2.5:p214 | 4.2.5:p215 | 4.2.5:p216 | 4.2.5:p217 | 4.2.5:p218 | 4.2.5:p219 | 4.2.5:p220 | 4.2.5:p221 | 4.2.5:p222 | 4.2.5:p223 | 4.2.5:p224 | 4.2.5:p225 | 4.2.5:p226 | 4.2.5:p227 | 4.2.5:p228 | 4.2.5:p229 | 4.2.5:p230 | 4.2.5:p231_rc1 | 4.2.5:p232_rc1 | 4.2.5:p233_rc1 | 4.2.5:p234_rc1 | 4.2.5:p235_rc1 | 4.2.5:p236_rc1 | 4.2.5:p237_rc1 | 4.2.5:p238_rc1 | 4.2.5:p239_rc1 | 4.2.5:p240_rc1 | 4.2.5:p241_rc1 | 4.2.5:p242_rc1 | 4.2.5:p243_rc1 | 4.2.5:p244_rc1 | 4.2.5:p245_rc1 | 4.2.5:p246_rc1 | 4.2.5:p247_rc1 | 4.2.5:p248_rc1 | 4.2.5:p249_rc1 | 4.2.5:p250_rc1 | 4.2.8:p1 | 4.2.8:p1-beta1 | 4.2.8:p1-beta2 | 4.2.8:p1-beta3 | 4.2.8:p1-beta4 | 4.2.8:p1-beta5 | 4.2.8:p1-rc1 | 4.2.8:p1-rc2 | 4.2.8:p2 | 4.2.8:p2-rc1 | 4.2.8:p2-rc2 | 4.2.8:p2-rc3 | 4.2.8:p3 | 4.2.8:p3-rc1 | 4.2.8:p3-rc2 | 4.2.8:p3-rc3
Ubuntu1 product
- ntp< 1:4.2.6.p5+dfsg-3ubuntu2.14.04.5
4 vendors · 9 products
References
17 links- bugzilla.redhat.com/show_bug.cgi?id=1274265X Refsource CONFIRMIssue TrackingThird Party AdvisoryVDB Entry
- h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05270839X Refsource CONFIRMThird Party AdvisoryVDB Entry
- cert-portal.siemens.com/productcert/pdf/ssa-497656.pdfX Refsource CONFIRM