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Fencer Vulns
medium 5.9

CVE-2019-19794 json

miekg/dns insecurely generates random numbers

published 2019-12-13 6 y ago modified 2026-06-17 4 mo ago also GHSA-44r7-7p62-q3fr , GO-2020-0008 , EUVD-2021-0929

cvss
5.9
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.1%
EPSS 2.1% chance of exploitation in 30 days, percentile 81%
public exploits
0
none known

Summary

The miekg Go DNS package before 1.1.25, as used in CoreDNS before 1.6.6 and other products, improperly generates random numbers because math/rand is used. The TXID becomes predictable, leading to response forgeries.

Patch / fix

  • go github.com/miekg/dns 1.1.25, 1.1.25-0.20191211073109-8ebf2e419df7
  • miekg-dns_project miekg-dns 1.1.25
  • golang-github-miekg-dns Debian 14, Debian 13, Debian 12 1.1.26-1

debian advisories DEBIAN-CVE-2019-19794

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2019-19794 updated cvss 5.9

golang-github-miekg-dns: predictable TXID can lead to response forgeries

  • Red Hat OpenStack Platform 16.2 osp-director-provisioner-container, rhosp-rhel8-tech-preview/osp-director-downloader
    affected: no fix available, no fix planned “Will not fix”
  • Red Hat OpenShift Jaeger 1.20 distributed-tracing/jaeger-rhel8-operator 1.20.1-3
    fixed: vendor fix RHSA-2020:5198
  • Red Hat OpenStack Platform 16.2 rhosp-rhel8-tech-preview/osp-director-operator 1.2.3-2
    fixed: vendor fix RHSA-2022:2183
  • Red Hat OpenShift Jaeger 1.20 distributed-tracing/jaeger-agent-rhel8 1.20.1-3, distributed-tracing/jaeger-query-rhel8 1.20.1-3, distributed-tracing/jaeger-ingester-rhel8 1.20.1-3, distributed-tracing/jaeger-collector-rhel8 1.20.1-3, distributed-tracing/jaeger-all-in-one-rhel8 1.20.1-3, distributed-tracing/jaeger-es-rollover-rhel8 1.20.1-3, +1 more Red Hat OpenStack Platform 16.2 rhosp-rhel8-tech-preview/osp-director-downloader 1.2.3-2, rhosp-rhel8-tech-preview/osp-director-operator-bundle 1.2.3-3
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

2.07% chance of exploitation in the next 30 days, higher than 81% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/miekg/dns/issues/1043 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
NVD 2.0 4.3 AV:N/AC:M/Au:N/C:N/I:P/A:N
GitHub 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected packages

ecosystem package affected fixed in
go github.com/miekg/dns
<1.1.25
<1.1.25-0.20191211073109-8ebf2e419df7
1.1.25
1.1.25-0.20191211073109-8ebf2e419df7

Classification

Weakness
  • CWE-338 Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
  • CWE-330 Use of Insufficiently Random Values

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.