Vulnerability in org.jenkins-ci.plugins:email-ext (CVE-2026-48920)
Summary
Vulnerability in org.jenkins-ci.plugins:email-ext (CVE-2026-48920). Successful exploitation can lead to full system takeover. Exploitable via base64. Mitigation: upgrade to 1933.1935.v276319e3cc47 or later.
Original description
The description as published by the source.
Jenkins Email Extension Plugin 1933.v45cec755423f and earlier allows inlining images as base64 in email content by setting the data-inline attribute, without restrictions on the image URLs that can be inlined, allowing attackers able to control the email content to specify file: URLs for images to read arbitrary files from the Jenkins controller filesystem.
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-2026-48920 has been found in org.jenkins-ci.plugins:email-ext.
Attackers can target a specific entry point like base64 over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 8.8/10.
What to do: upgrade org.jenkins-ci.plugins:email-ext to 1933.1935.v276319e3cc47 or later.
If unsure, ask your IT team or search "org.jenkins-ci.plugins:email-ext CVE-2026-48920" on the vendor's site.
CVE-2026-48920 (org.jenkins-ci.plugins:email-ext) — CWE-73 / CVSS v3 8.8
Attack vector: remote (network-reachable) / no user interaction
Attack surface: base64
Patched: 1933.1935.v276319e3cc47 — 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.
A vulnerability (CWE-73) exists in org.jenkins-ci.plugins:email-ext. Attackers reach the vulnerable code path via base64.
Check the vendor advisory for the affected versions of org.jenkins-ci.plugins:email-ext. Attack surface: base64.
Severity: High (CVSS 8.8/10). Successful exploitation can lead to full system takeover.
Update to 1933.1935.v276319e3cc47.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies 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
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで org.jenkins-ci.plugins:email-ext を使っているサービスとバージョンを洗い出す。
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2Apply patch patch
Upgrade org.jenkins-ci.plugins:email-ext to 1933.1935.v276319e3cc47ステージング環境で 1933.1935.v276319e3cc47 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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3Post-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
References
- advisory nvd.nist.gov
- package github.com
- patch jenkinsci-cert@googlegroups.com
- web github.com