Malicious PDF — malware analysis report

Static analysis result for SHA-256 631437c4de4c4444…

MALICIOUS

PDF

17.3 KB
MD5: be79e46c6feacd74a9688d8ed5add7dc SHA-1: 22b0f1863c3ddb7484aee7f177f79c3aeebaf5b1 SHA-256: 631437c4de4c4444ebfe987136456e5ab501b33f8793bfbc3c8d3da0c975cd6f
366 Risk Score

Malware Insights

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

The PDF contains obfuscated JavaScript that exploits CVE-2007-5659 in Adobe Reader. The script is designed to download and execute a second-stage payload from the embedded URL 'http://moneymagcoach.com/news/data.html?ID=20677&fb=WVRveU9udHpPamc2SW5WelpYSmtZWFJoSWp0aE9qTTZlM002TWpvaWFXUWlPM002TnpvaU9EQXdNekV3TWlJN2N6b3hNam9pWVdSMlpYSjBhWE5sWDJsa0lqdHpPalk2SWpFd01qRXlOQ0k3Y3pvME9pSnJjSEJwSWp0T08zMXpPak02SW0xa05TSTdjem96TWpvaVlqQTJZMlZtTXpKaE4ySXdNR1V6TnpJMVpEQXdaRGM1WXpJME9HRXhZV01pTzMwPQ%3D%3D/n002106201r0409Rd964e288X3ae949dbY08b46c66Z0100f070'. This indicates a dropper functionality aimed at delivering further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 12

  • 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 static 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.
  • ClamAV: Pdf.Exploit.Agent-35901 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35901
  • Obfuscated multi-stage PDF JavaScript dropper high PDF_JS_OBFUSCATED_DROPPER
    PDF JavaScript shows 5 independent signals of exploit-kit-style multi-stage obfuscation: annot_subject_stage, hex_codec_loop, hex_dashed_payload, incremental_eval_build, repeated_pluginschk. This is strongly consistent with pre-2011 Adobe Reader PDF droppers — OpenAction JS reads encoded data from annotation subjects, decodes it through one or more hex / base-N loops, and invokes eval indirectly (method name built one character at a time). The actual CVE is hidden in the final decoded layer and is not visible via static analysis.
  • 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)
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed 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://moneymagcoach.com/news/data.html?ID=20677&fb=WVRveU9udHpPamc2SW5WelpYSmtZWFJoSWp0aE9qTTZlM002TWpvaWFXUWlPM002TnpvaU9EQXdNekV3TWlJN2N6b3hNam9pWVdSMlpYSjBhWE5sWDJsa0lqdHpPalk2SWpFd01qRXlOQ0k3Y3pvME9pSnJjSEJwSWp0T08zMXpPak02SW0xa05TSTdjem96TWpvaVlqQTJZMlZtTXpKaE4ySXdNR1V6TnpJMVpEQXdaRGM1WXpJME9HRXhZV01pTzMwPQ%3D%3D/n002106201r0409Rd964e288X3ae949dbY08b46c66Z0100f070

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0005_000.js
4718a27c2224fc36bf24f8e8e04598f1ad78adce4401c7be2708318738a6983d
pdf-javascript-stream PDF /JS object 5 at offset 0x148 469 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
398e634144e537080749856ef88ad5ba0c091c6f6fbef22c0ad20ccfdb75e461
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x1D50 13845 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
288f7dfadf5832ff7691ef327e2c9403a02c9ba61e2d273a8e32a1375ebdede5
deobfuscated-js nested inline base-23 callee-key decoded JavaScript at offset 0x1D50 5639 bytes
deobfuscated.js
66c733d2f877fa4126237d5febbccd61a724015fa4ac68be8bf2461ed51ba453
deobfuscated-js PDF JavaScript deobfuscation pass 140506 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 10 eval/decoder/string-building token(s). Carved artifact contains 2 long base64-like blob(s).