uClibc-ng through 1.0.40 and uClibc through 0.9.33.2 use predictable DNS transaction IDs that may lead to DNS cache poisoning.

published 2022-05-06 4 y ago modified 2026-06-17 4 mo ago also EUVD-2022-52246

cvss: 6.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 11.2%; EPSS 11.2% chance of exploitation in 30 days, percentile 95%
public exploits: 0; none known

uClibc-ng through 1.0.40 and uClibc through 0.9.33.2 use predictable DNS transaction IDs that may lead to DNS cache poisoning. This is related to a reset of a value to 0x2.

Patch / fix

distros 1

uclibc-ng CBL-Mariner 2.0 1.0.41-1

azure linux advisories AZL-9702

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Exploit prediction

11.21% chance of exploitation in the next 30 days, higher than 95% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	6.5	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
NVD	2.0	4.0	AV:N/AC:H/Au:N/C:P/I:P/A:N

Classification

Weakness

CWE-330 Use of Insufficiently Random Values

References

nozominetworks.com /blog/nozomi-networks-discovers-unpatched-dns-bug-in-popular-c-standard-library-putting-iot-at-risk/
third-party-advisory
kb.cert.org /vuls/id/473698
third-party-advisory, us-government-resource

Sources

CVE List CVE-2022-30295
NVD CVE-2022-30295

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.

Summary