How severe is CVE-2023-45139?

CVE-2023-45139 has a CVSS 3.x base score of 7.5, rated high 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 none.

Is CVE-2023-45139 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-45139?

CVE-2023-45139 affects Fonttools. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-45139?

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

Does CVE-2023-45139 have an EU (EUVD) identifier?

Yes. CVE-2023-45139 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0267.

When was CVE-2023-45139 published?

CVE-2023-45139 was published on 2024-01-10 and last updated on 2026-06-17.

CVE-2023-45139

CVE-2023-45139 is a high-severity vulnerability in Fonttools with a CVSS 3.x base score of 7.5. 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-611.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-0267
Weakness: CWE-611
Affected product: Fonttools
Published: 2024-01-10
Last modified: 2026-06-17

Description

fontTools is a library for manipulating fonts, written in Python. The subsetting module has a XML External Entity Injection (XXE) vulnerability which allows an attacker to resolve arbitrary entities when a candidate font (OT-SVG fonts), which contains a SVG table, is parsed. This allows attackers to include arbitrary files from the filesystem fontTools is running on or make web requests from the host system. This vulnerability has been patched in version 4.43.0.

Frequently asked questions

What is CVE-2023-45139?: fontTools is a library for manipulating fonts, written in Python. The subsetting module has a XML External Entity Injection (XXE) vulnerability which allows an attacker to resolve arbitrary entities when a candidate font (OT-SVG fonts), which contains a SVG table, is parsed. This allows attackers to include arbitrary files from the filesystem fontTools is running on or make web requests from the host system. This vulnerability has been patched in version 4.43.0.
How severe is CVE-2023-45139?: CVE-2023-45139 has a CVSS 3.x base score of 7.5, rated high 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 none.
Is CVE-2023-45139 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-45139?: CVE-2023-45139 affects Fonttools. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-45139?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2023-45139 have an EU (EUVD) identifier?: Yes. CVE-2023-45139 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0267.
When was CVE-2023-45139 published?: CVE-2023-45139 was published on 2024-01-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fonttools:fonttools:*:*:*:*:*:python:*:*

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