How severe is CVE-2026-34085?

CVE-2026-34085 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-34085 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34085?

CVE-2026-34085 affects Fontconfig Project Fontconfig. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34085?

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

Does CVE-2026-34085 have an EU (EUVD) identifier?

Yes. CVE-2026-34085 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-15934.

When was CVE-2026-34085 published?

CVE-2026-34085 was published on 2026-03-25 and last updated on 2026-06-17.

CVE-2026-34085

CVE-2026-34085 is a medium-severity vulnerability in Fontconfig Project Fontconfig with a CVSS 3.x base score of 5.9. 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-193.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-15934
Weakness: CWE-193
Affected product: Fontconfig Project Fontconfig
Published: 2026-03-25
Last modified: 2026-06-17

Description

fontconfig before 2.17.1 has an off-by-one error in allocation during sfnt capability handling, leading to a one-byte out-of-bounds write, and potentially a crash or code execution. This is in FcFontCapabilities in fcfreetype.c.

Frequently asked questions

What is CVE-2026-34085?: fontconfig before 2.17.1 has an off-by-one error in allocation during sfnt capability handling, leading to a one-byte out-of-bounds write, and potentially a crash or code execution. This is in FcFontCapabilities in fcfreetype.c.
How severe is CVE-2026-34085?: CVE-2026-34085 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-34085 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34085?: CVE-2026-34085 affects Fontconfig Project Fontconfig. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34085?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-34085 have an EU (EUVD) identifier?: Yes. CVE-2026-34085 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-15934.
When was CVE-2026-34085 published?: CVE-2026-34085 was published on 2026-03-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fontconfig_project:fontconfig:2.17.0:*:*:*:*:*:*:*

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