How severe is CVE-2023-49991?

CVE-2023-49991 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2023-49991 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-49991?

CVE-2023-49991 affects Espeak-ng. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-49991?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-49991 published?

CVE-2023-49991 was published on 2023-12-12 and last updated on 2026-06-17.

CVE-2023-49991

CVE-2023-49991 is a medium-severity vulnerability in Espeak-ng with a CVSS 3.x base score of 5.3. 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-787.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Espeak-ng
Published: 2023-12-12
Last modified: 2026-06-17

Description

Espeak-ng 1.52-dev was discovered to contain a Stack Buffer Underflow via the function CountVowelPosition at synthdata.c.

Frequently asked questions

What is CVE-2023-49991?: Espeak-ng 1.52-dev was discovered to contain a Stack Buffer Underflow via the function CountVowelPosition at synthdata.c.
How severe is CVE-2023-49991?: CVE-2023-49991 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2023-49991 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-49991?: CVE-2023-49991 affects Espeak-ng. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-49991?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-49991 published?: CVE-2023-49991 was published on 2023-12-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:espeak-ng:espeak-ng:1.52:dev:*:*:*:*:*:*

More vulnerabilities in Espeak-ng

CVE-2023-49994 — Medium (CVSS 5.5): Espeak-ng 1.52-dev was discovered to contain a Floating Point Exception via the function PeaksToHarmspect at wavegen.c.
CVE-2023-49993 — Medium (CVSS 5.3): Espeak-ng 1.52-dev was discovered to contain a Buffer Overflow via the function ReadClause at readclause.c.
CVE-2023-49992 — Medium (CVSS 5.3): Espeak-ng 1.52-dev was discovered to contain a Stack Buffer Overflow via the function RemoveEnding at dictionary.c.
CVE-2023-49990 — Medium (CVSS 5.3): Espeak-ng 1.52-dev was discovered to contain a buffer-overflow via the function SetUpPhonemeTable at synthdata.c.

All CVEs affecting Espeak-ng →

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