How severe is CVE-2019-9748?

CVE-2019-9748 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2019-9748 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-9748?

CVE-2019-9748 affects Tinysvcmdns Project Tinysvcmdns. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-9748?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2019-9748 published?

CVE-2019-9748 was published on 2019-03-13 and last updated on 2026-06-17.

CVE-2019-9748

CVE-2019-9748 is a critical-severity vulnerability in Tinysvcmdns Project Tinysvcmdns with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v2: 9.4
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Tinysvcmdns Project Tinysvcmdns
Published: 2019-03-13
Last modified: 2026-06-17

Description

In tinysvcmdns through 2018-01-16, an mDNS server processing a crafted packet can perform arbitrary data read operations up to 16383 bytes from the start of the buffer. This can lead to a segmentation fault in uncompress_nlabel in mdns.c and a crash of the server (depending on the memory protection of the CPU and the operating system), or disclosure of memory content via error messages or a server response. NOTE: the product's web site states "This project is un-maintained, and has been since 2013. ... There are known vulnerabilities ... You are advised to NOT use this library for any new projects / products."

Frequently asked questions

What is CVE-2019-9748?: In tinysvcmdns through 2018-01-16, an mDNS server processing a crafted packet can perform arbitrary data read operations up to 16383 bytes from the start of the buffer. This can lead to a segmentation fault in uncompress_nlabel in mdns.c and a crash of the server (depending on the memory protection of the CPU and the operating system), or disclosure of memory content via error messages or a server response. NOTE: the product's web site states "This project is un-maintained, and has been since 2013. ... There are known vulnerabilities ... You are advised to NOT use this library for any new projects / products."
How severe is CVE-2019-9748?: CVE-2019-9748 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2019-9748 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-9748?: CVE-2019-9748 affects Tinysvcmdns Project Tinysvcmdns. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-9748?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2019-9748 published?: CVE-2019-9748 was published on 2019-03-13 and last updated on 2026-06-17.

References

https://bitbucket.org/geekman/tinysvcmdns/issues/10/arbitrary-memory-read-while-parsing

Affected products (1)

cpe:2.3:a:tinysvcmdns_project:tinysvcmdns:*:*:*:*:*:*:*:*

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