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CVE-2013-0256

CVE-2013-0256 is a Cross-site Scripting (XSS) vulnerability in canonical ubuntu linux. O3 Security detects and blocks CVE-2013-0256 exploitation at runtime via eBPF exploit-chain detection and L7 egress monitoring, even on unpatched systems.

darkfish.js in RDoc 2.3.0 through 3.12 and 4.x before 4.0.0.preview2.1, as used in Ruby, does not properly generate documents, which allows remote attackers to conduct cross-site scripting…

Published
Mar 1, 2013
Updated
Jun 16, 2026
Affected
0 pkgs
Patched
None yet
Exploits
None indexed

Description

darkfish.js in RDoc 2.3.0 through 3.12 and 4.x before 4.0.0.preview2.1, as used in Ruby, does not properly generate documents, which allows remote attackers to conduct cross-site scripting (XSS) attacks via a crafted URL.

Affected Products

3 products · 17 configurations
OS
ubuntu linuxcanonical
2 versions
12.0412.10
Application
rdocruby-lang
≥ 2.3.0 && < 3.12
1 version
4.0.0
Application
rubyruby-lang
6 versions
1.91.9.11.9.21.9.32.02.0.0

Detection & mitigation playbook

Vendor / appliance
  1. Detect

    Inventory every canonical ubuntu linux deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.

  2. Fix

    Apply the canonical ubuntu linux security patch or hotfix for CVE-2013-0256 on the affected version, following the vendor advisory for your exact build.

  3. Workarounds

    Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.

  4. How O3 protects you

    O3 detects and blocks CVE-2013-0256 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Tailored to CVE-2013-0256. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

darkfish.js in RDoc 2.3.0 through 3.12 and 4.x before 4.0.0.preview2.1, as used in Ruby, does not properly generate documents, which allows remote attackers to conduct cross-site scripting (XSS) attacks via a crafted URL.
O3 Security · Runtime Protection

Is CVE-2013-0256 being exploited in your environment?

O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2013-0256 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.