Path Traversal in com.github.jknack:handlebars-springmvc (CVE-2026-63490)
Summary
Path traversal in com.github.jknack:handlebars-springmvc (CVE-2026-63490). Confidential information can be exposed externally. Exploitable via ResourceLoader. Mitigation: upgrade to 4.5.3 or later.
Original description
The description as published by the source.
Handlebars.java provides logic-less and semantic Mustache templates with Java. Prior to 4.5.3, com.github.jknack.handlebars.springmvc.SpringTemplateLoader resolves attacker-influenced Spring MVC view names through Spring ResourceLoader without the path-containment validation used by other URL-based loaders. In handlebars-springmvc/src/main/java/com/github/jknack/handlebars/springmvc/SpringTemplateLoader.java, a view name using a file: or classpath: URL and ending with the # fragment delimiter places the appended .hbs suffix in the fragment, which FileUrlResource.exists() and URL.openStream() discard. HandlebarsViewResolver in handlebars-springmvc/src/main/java/com/github/jknack/handlebars/springmvc/HandlebarsViewResolver.java then passes the attacker-controlled name to handlebars.compile(), allowing an unauthenticated remote attacker to read files accessible to the JVM when an application exposes a controller with a user-influenced view name. This issue is fixed in version 4.5.3.
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-2026-63490 has been found in com.github.jknack:handlebars-springmvc.
Attackers can target a specific entry point like ResourceLoader over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 7.5/10.
What to do: upgrade com.github.jknack:handlebars-springmvc to 4.5.3 or later.
If unsure, ask your IT team or search "com.github.jknack:handlebars-springmvc CVE-2026-63490" on the vendor's site.
CVE-2026-63490 (com.github.jknack:handlebars-springmvc) — CWE-22 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: ResourceLoader / ClassPathTemplateLoader / FileTemplateLoader / ServletContextTemplateLoader
Patched: 4.5.3 — 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.
Path traversal (CWE-22) exists in com.github.jknack:handlebars-springmvc. Attackers reach the vulnerable code path via ResourceLoader without authentication.
Check the vendor advisory for the affected versions of com.github.jknack:handlebars-springmvc. Attack surface: ResourceLoader / ClassPathTemplateLoader / FileTemplateLoader / ServletContextTemplateLoader.
Severity: High (CVSS 7.5/10). Confidential information can be exposed externally.
Update to 4.5.3.
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 com.github.jknack:handlebars-springmvc 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 com.github.jknack:handlebars-springmvc to 4.5.3ステージング環境で 4.5.3 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 github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com
- web github.com
- web github.com