Malicious PDF — malware analysis report

Static analysis result for SHA-256 199c5edfd1da1c81…

MALICIOUS

PDF

8.1 KB
MD5: 294fcae39204e95f79181e6f13afa3c5 SHA-1: f734024c0d6eda9303d43c375ac2f9e8e1247cf2 SHA-256: 199c5edfd1da1c8145a99de2e0b8eb929889db0e9045e91a3dafa5253e291055
298 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains embedded JavaScript that exploits CVE-2007-5659, specifically targeting Adobe Reader versions that are not patched against APSB08-13. The script is designed to download a second-stage payload from the URL http://googleinru.in/cgi-bin/etn/z002106201r0019R97f3b4e5X616520b3Y7a5cffe7Z0100f060. The use of eval() and String.fromCharCode() indicates obfuscation, common in exploit delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 10

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • Adobe Reader APSB08-13 patch-range version gate (CVE-2007-5659) high CVE likely PDF_JS_ADOBE_APSB08_13_PATCH_GATE
    PDF JavaScript gates the exploit payload on (>= 8 && < 8.1.1) OR (< 7.1) — the Reader 7.0.x / 8.0–8.1.1 window patched by Adobe APSB08-13 for the CVE-2007-5659 Collab.collectEmailInfo buffer overflow. Only kits that target that exact bug check both of those patch points; benign scripts do not.
  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • PDF JavaScript shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL
    Decoded PDF JavaScript shellcode contains a hardcoded http(s) URL stored as little-endian %uXXXX Unicode escapes. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://googleinru.in/cgi-bin/etn/z002106201r0019R97f3b4e5X616520b3Y7a5cffe7Z0100f060

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0004_000.js
56bc8fc47dd90bd2399d356c5c3c0a451c8615650973dbea43cf343f0252f7cb
pdf-javascript-stream PDF /JS object 4 at offset 0xE1 313 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
d02c92d14afce1842f35fca3eabab64ba47c2eee12ad1688a00505acfe0e5fbb
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x1B1F 1777 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
47a790f8cdf1ea9d02a3dde8f767054807722d2a13d65a8ec2bf83350f2cc334
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x35F 5060 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).