Vulnerability in thumbor (UBUNTU-CVE-2026-53505)

Summary

Vulnerability in thumbor (UBUNTU-CVE-2026-53505). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 7.8.0 or later.

Original description

The description as published by the source.

Thumbor is an open-source photo thumbnail service by globo.com. Prior to 7.8.0, Thumbor's filters:proportion() filter does not enforce an upper bound on and runs in the post-transform phase. An attacker can trigger extremely large resizes (CPU/memory exhaustion) and cause denial of service. This issue is fixed in 7.8.0.

Source: OSV.dev (Open Source Vulnerabilities) OSV

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 UBUNTU-CVE-2026-53505 has been found in thumbor.
Risk of unauthorized operations or information disclosure.
What to do: upgrade thumbor to 7.8.0 or later.
If unsure, ask your IT team or search "thumbor UBUNTU-CVE-2026-53505" on the vendor's site.

UBUNTU-CVE-2026-53505 (thumbor)
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 7.8.0 — apply immediately
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.

❓ What is the problem

A vulnerability (unclassified) exists in thumbor.

📍 Affected scope

Check the vendor advisory for the affected versions of thumbor.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 7.8.0.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'thumbor' . 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

1
Identify exposure identify
```
grep -r 'thumbor' . | 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 thumbor を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade thumbor to 7.8.0
```
ステージング環境で 7.8.0 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。
3
Post-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

Ubuntu:26.04:LTS thumbor

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

References

report ubuntu.com
report cve.org
report github.com
report github.com
report github.com