Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c418e25f22b25be…

MALICIOUS

PDF

12.1 KB
MD5: 966432f487362b67fefecd3937feb9f0 SHA-1: 36e21f9eb90ea05b1674ab5c726cd3737d5200d5 SHA-256: 7c418e25f22b25beb0090325ca01a3d8f3aefea496a32d732b2f1e9b8bd5cfbc
198 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1071.001 Web Protocols

The PDF file contains obfuscated JavaScript, identified by critical heuristics like 'PDF_ANNOT_SUBJECT_MARKER_EVAL_STAGER' and 'CVE_2007_5659'. These heuristics indicate the exploitation of a known Adobe Reader vulnerability (CVE-2007-5659) using the 'Collab.collectEmailInfo' function to execute a stager. The stager, found in the extracted JavaScript files 'legacy_pdfkit_stage_000.js' and 'legacy_pdfkit_stage_001.js', is designed to download and execute a second-stage payload, indicating a typical downloader pattern.

Heuristics 6

  • 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)
  • Annotation subject percent-decoding eval stager critical PDF_ANNOT_SUBJECT_MARKER_EVAL_STAGER
    OpenAction JavaScript forces annotation enumeration, reads an annotation /Subject payload with getAnnots(), rewrites marker bytes into percent escapes, decodes it with unescape(), and dispatches it through eval. This is a high-confidence exploit-kit staging pattern. It is intentionally not mapped to CVE-2009-1492 unless getAnnots() itself carries the crafted integer or long argument shape for that vulnerability.
  • ClamAV: Heuristics.PDF.ObfuscatedNameObject critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Heuristics.PDF.ObfuscatedNameObject
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
6f60a1053baafdc578f85eae84a2dc6d16775fbd66240d82cbfb7b4f4ff4e90a
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 295 bytes
legacy_pdfkit_stage_000.js
3bc5e2e028f69e838d4bdb8bcc22a01a7a46a99b6cbb8d4af6a529ccfefab978
deobfuscated-js z-percent hex-pair decoded JavaScript at offset 0x2E9 5116 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
7678f9ea29fe3f47b487773d071727dff4a91d04ec06d8871811338f796cece0
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2E9 12308 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).