Vulnerability in pillow (CVE-2026-42310)
Summary
Vulnerability in pillow (CVE-2026-42310). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 12.2.0 or later.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-42310 has been found in pillow.
Risk of unauthorized operations or information disclosure. CVSS score: 5.5/10.
What to do: upgrade pillow to 12.2.0 or later.
If unsure, ask your IT team or search "pillow CVE-2026-42310" on the vendor's site.
CVE-2026-42310 (pillow) — CWE-835 / CVSS v3 5.5
Attack vector: local / no user interaction
Patched: 12.2.0 — apply immediately
Workaround: Use any version but the affected versions: >= 4.2.0, < 12.2.0
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-835) exists in pillow.
Check the vendor advisory for the affected versions of pillow.
Severity: Medium (CVSS 5.5/10). Risk of unauthorized operations or information disclosure.
Update to 12.2.0.
Workaround: Use any version but the affected versions: >= 4.2.0, < 12.2.0
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'pillow' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'pillow' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
pillowを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply temporary workaround mitigate
Use any version but the affected versions: >= 4.2.0, < 12.2.0パッチが適用されるまでの応急処置として、Use any version but the affected versions: >= 4.2.0, < 12.2.0 を実施。回避策の副作用 (機能低下) を確認した上で。
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3Apply patch patch
Upgrade pillow to 12.2.0ステージング環境で 12.2.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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4Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-42310 pillow
- Ubuntu UBUNTU-CVE-2026-42310 pillow
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com
- patch github.com
- web github.com
- web github.com