Malicious PDF — malware analysis report

Static analysis result for SHA-256 798e3e6003b77e18…

MALICIOUS

PDF

7.6 KB
MD5: 8204dfdd304fcaa15290d2dfd0879aa9 SHA-1: d519be2d808bb2fca484856e0a7f543bbe35510f SHA-256: 798e3e6003b77e18954c3735505d472bc1f40d8b576aa8a1c104ebbb1881b510
368 Risk Score

Malware Insights

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

The PDF sample contains heavily obfuscated JavaScript, indicated by multiple heuristic firings including PDF_OBFUSCATED_NAME_OBJECT and PDF_JS_EXPLOIT_CLUSTER. The script utilizes unescape() and exploits CVE-2009-0927 (Collab.getIcon) to achieve code execution. The deobfuscated JavaScript likely acts as a downloader for a subsequent payload, although the exact URL is not directly visible due to the obfuscation.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 9

  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (matched in decompressed stream)
  • Hex-obfuscated scripting name object critical PDF_OBFUSCATED_NAME_OBJECT
    A PDF name object that drives script execution (/JavaScript or /JS) is written with #XX hex escapes to hide it from string-based scanners — e.g. /J#61v#61S#63r#69p#74 decoding to /JavaScript. Legitimate PDF producers always write these names literally; hex-encoding an executable name is a deliberate evasion used by exploit-kit and dropper PDFs.
  • 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.
  • ClamAV: Heuristics.PDF.ObfuscatedNameObject critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Heuristics.PDF.ObfuscatedNameObject
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • Generic recovered JavaScript exploit stage high PDF_GENERIC_STAGE_RECOVERY
    Bounded static stage recovery exposed hidden JavaScript through generic transforms such as null-byte collapse, percent decoding, marker replacement, arithmetic character codes, fromCharCode, numeric arrays, numeric-array minus-key decoders, alphabet-index arrays, /Producer half-difference metadata arrays, hex literals, marker-stripped Base64 literals, custom 6-bit XOR table decoders, or repeated-marker hex carriers. This rule is emitted only when the recovered stage contains exploit-like Acrobat JavaScript or shellcode markers.
  • 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.
  • 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.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
3c1d57893288d7d5bfe626b2ac2c94de552f80b20d2d185ceacdae40968c6d81
pdf-javascript-stream PDF /JS object 6 at offset 0x1A7 6524 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
generic_stage_recovery_000.js
ff941edd0715dfe01773eb393b7d7bb5c8ab215127948cf7fe712eadfeca3f23
deobfuscated-js generic stage recovery percent-decode from JavaScript object 6 at offset 0x1A7 6522 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 4 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).