How severe is CVE-2026-42310?

CVE-2026-42310 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-42310 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-2026-42310?

CVE-2026-42310 affects Python Pillow. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-42310?

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

Does CVE-2026-42310 have an EU (EUVD) identifier?

Yes. CVE-2026-42310 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28902.

When was CVE-2026-42310 published?

CVE-2026-42310 was published on 2026-05-09 and last updated on 2026-06-17.

CVE-2026-42310

CVE-2026-42310 is a medium-severity vulnerability in Python Pillow with a CVSS 3.x base score of 5.5. 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-835.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v4: 5.1
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-28902
Weakness: CWE-835
Affected product: Python Pillow
Published: 2026-05-09
Last modified: 2026-06-17

Description

Pillow is a Python imaging library. From version 4.2.0 to before version 12.2.0, an attacker can supply a malicious PDF that causes the process to hang indefinitely, consuming 100% CPU and making the application unresponsive. This issue has been patched in version 12.2.0.

Frequently asked questions

What is CVE-2026-42310?: Pillow is a Python imaging library. From version 4.2.0 to before version 12.2.0, an attacker can supply a malicious PDF that causes the process to hang indefinitely, consuming 100% CPU and making the application unresponsive. This issue has been patched in version 12.2.0.
How severe is CVE-2026-42310?: CVE-2026-42310 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-42310 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-2026-42310?: CVE-2026-42310 affects Python Pillow. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42310?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-42310 have an EU (EUVD) identifier?: Yes. CVE-2026-42310 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28902.
When was CVE-2026-42310 published?: CVE-2026-42310 was published on 2026-05-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:*

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