How severe is CVE-2026-42311?

CVE-2026-42311 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-42311 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42311?

CVE-2026-42311 affects Python Pillow. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-42311?

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-2026-42311 have an EU (EUVD) identifier?

Yes. CVE-2026-42311 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28903.

When was CVE-2026-42311 published?

CVE-2026-42311 was published on 2026-05-09 and last updated on 2026-06-17.

CVE-2026-42311

CVE-2026-42311 is a high-severity vulnerability in Python Pillow with a CVSS 3.x base score of 7.8. 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-190.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v4: 8.6
EPSS exploit prediction: 0% (5th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-28903
Weakness: CWE-190
Affected product: Python Pillow
Published: 2026-05-09
Last modified: 2026-06-17

Description

Pillow is a Python imaging library. From version 10.3.0 to before version 12.2.0, processing a malicious PSD file could lead to memory corruption, potentially resulting in a crash or arbitrary code execution. This issue has been patched in version 12.2.0.

Frequently asked questions

What is CVE-2026-42311?: Pillow is a Python imaging library. From version 10.3.0 to before version 12.2.0, processing a malicious PSD file could lead to memory corruption, potentially resulting in a crash or arbitrary code execution. This issue has been patched in version 12.2.0.
How severe is CVE-2026-42311?: CVE-2026-42311 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-42311 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42311?: CVE-2026-42311 affects Python Pillow. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42311?: 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-2026-42311 have an EU (EUVD) identifier?: Yes. CVE-2026-42311 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28903.
When was CVE-2026-42311 published?: CVE-2026-42311 was published on 2026-05-09 and last updated on 2026-06-17.

References

Affected products (1)

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

More vulnerabilities in Python Pillow

CVE-2014-3007 — Critical (CVSS 10.0): Python Image Library (PIL) 1.1.7 and earlier and Pillow 2.3 might allow remote attackers to execute arbitrary commands…
CVE-2022-30595 — Critical (CVSS 9.8): libImaging/TgaRleDecode.c in Pillow 9.1.0 has a heap buffer overflow in the processing of invalid TGA image files.
CVE-2022-22817 — Critical (CVSS 9.8): PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python…
CVE-2021-34552 — Critical (CVSS 9.8): Pillow through 8.2.0 and PIL (aka Python Imaging Library) through 1.1.7 allow an attacker to pass controlled parameters…
CVE-2021-25289 — Critical (CVSS 9.8): An issue was discovered in Pillow before 8.1.1. TiffDecode has a heap-based buffer overflow when decoding crafted YCbCr…
CVE-2020-5312 — Critical (CVSS 9.8): libImaging/PcxDecode.c in Pillow before 6.2.2 has a PCX P mode buffer overflow.

All CVEs affecting Python Pillow →

Other CWE-190 (Integer Overflow or Wraparound) vulnerabilities

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CVE-2025-64721 — Critical (CVSS 10.0): Sandboxie is a sandbox-based isolation software for 32-bit and 64-bit Windows NT-based operating systems. In versions…
CVE-2015-5108 — Critical (CVSS 10.0): Integer overflow in Adobe Reader and Acrobat 10.x before 10.1.15 and 11.x before 11.0.12, Acrobat and Acrobat Reader DC…
CVE-2015-5097 — Critical (CVSS 10.0): Integer overflow in Adobe Reader and Acrobat 10.x before 10.1.15 and 11.x before 11.0.12, Acrobat and Acrobat Reader DC…
CVE-2013-2555 — Critical (CVSS 10.0): Integer overflow in Adobe Flash Player before 10.3.183.75 and 11.x before 11.7.700.169 on Windows and Mac OS X, before…

Browse all CWE-190 (Integer Overflow or Wraparound) vulnerabilities →