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Fencer Vulns
low 3.7

CVE-2023-41045 json

Insecure source port usage for DNS queries in Graylog

published 2023-07-06 3 y ago modified 2026-06-17 4 mo ago also GHSA-g96c-x7rh-99r3 , EUVD-2023-2058

cvss
3.7
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 29%
public exploits
0
none known

Summary

Graylog is a free and open log management platform. Graylog makes use of only one single source port for DNS queries. Graylog binds a single socket for outgoing DNS queries and while that socket is bound to a random port number it is never changed again. This goes against recommended practice since 2008, when Dan Kaminsky discovered how easy is to carry out DNS cache poisoning attacks. In order to prevent cache poisoning with spoofed DNS responses, it is necessary to maximise the uncertainty in the choice of a source port for a DNS query. Although unlikely in many setups, an external attacker could inject forged DNS responses into a Graylog's lookup table cache. In order to prevent this, it is at least recommendable to distribute the DNS queries through a pool of distinct sockets, each of them with a random source port and renew them periodically. This issue has been addressed in versions 5.0.9 and 5.1.3. Users are advised to upgrade. There are no known workarounds for this issue.

Patch / fix

  • maven org.graylog2:graylog2-server 5.0.9, 5.1.3
  • graylog graylog 5.0.9, 5.1.3

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

0.36% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/Graylog2/graylog2-server/security/advisories/GHSA-g96c-x7rh-99r3 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
NVD 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
GitHub 3.1 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected packages

ecosystem package affected fixed in
maven org.graylog2:graylog2-server
>=5.1.0, <5.1.3
<5.0.9
5.1.3
5.0.9

Affected products

  • Graylog2 graylog2-server

Classification

Weakness
  • CWE-345 Insufficient Verification of Data Authenticity

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.