Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e0df772d2bee660…

MALICIOUS

PDF

11.8 KB
MD5: 4f75f04cc77b26d34fdc23efefa302e0 SHA-1: bae4461edce6f14d256f4341dee24ce61ec7497f SHA-256: 9e0df772d2bee6601c5801e88c5342a9289d7fa9e6f115c9008f53d6e650558d
200 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1027 Obfuscated Files or Information

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT and PDF_JS. Critical heuristics like PDF_ANNOT_SUBJECT_MARKER_EVAL_STAGER and CVE_2007_5659 point to the use of JavaScript for exploitation, specifically leveraging the 'Collab.collectEmailInfo' method with obfuscated code. ClamAV also identified this as Pdf.Exploit.Agent-36065. The embedded JavaScript streams, particularly legacy_pdfkit_stage_000.js and legacy_pdfkit_stage_001.js, suggest a multi-stage attack involving obfuscation to download and execute further payloads.

Heuristics 7

  • 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: Pdf.Exploit.Agent-36065 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36065
  • 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.
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser exited 1. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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
9c67560e8c63b720885d3efc1627b844b86a6ec08e99e5b65a22eae832045756
pdf-javascript-stream PDF /JS object 7 at offset 0x19C 431 bytes
legacy_pdfkit_stage_000.js
a0a06a3a3472029422941da86807bce4efc60bccb254e21368f989e4dd4f6cf3
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 12038 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
87d87fde2d4ce168f03393b2775e7bd78bc26292d3b869b6f49ba6aeaf69eb7a
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 4965 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).