Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1bb3b71e842c448…

MALICIOUS

PDF

72.2 KB Created: 2021-07-12 22:37:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 27c5697c8089c58d06c5dbb6a4f0f3bd SHA-1: 514d1b18b2d6a96b5b34c41a91e653323eec9950 SHA-256: d1bb3b71e842c448e581a4d34dda1ae58913ac4f24c70f6cb3aab0cf1b923fe8
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of an external URI pointing to 'crewmak.ru' suggests a download or redirection attempt. The 'SE_DOWNLOAD_BUTTON' heuristic further supports the idea that the document is designed to trick users into initiating a download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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 https://crewmak.ru/square?utm_term=past+simple+mixed+exercises+online
    • https://static1.squarespace.com/static/60aac59fb7e9621e2f466549/t/60ec806c7e5cd11affccd2e0/1626112108550/68019125421.pdf
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60e8f65ac91b61347ea1ce67/1625880154998/forms_of_bind.pdf
    • https://static1.squarespace.com/static/60bf6bff0d8d387fecc8b153/t/60ec8d95f918372873877bab/1626115477684/89193564131.pdf
    • https://static1.squarespace.com/static/60bf6c89a2b0b938881bcf91/t/60e76bf54e14410b5d336064/1625779189223/piano_notes_for_perfect.pdf
    • https://static1.squarespace.com/static/60aac5994c6b1805bc4acbdb/t/60e92f2d2c5c2f6215c97cb2/1625894701209/41634323856.pdf
    • https://static1.squarespace.com/static/60aac4dd19f082755c4e5c69/t/60ec805d0d838b6c850c990d/1626112093677/79068868427.pdf
    • https://static1.squarespace.com/static/60bf6cad3a95e91b59aa2418/t/60e8cc41f311dc752b0ad832/1625869377316/56317881628.pdf
    • https://static1.squarespace.com/static/60aac52a97a1d73ddacfe14c/t/60ec7122154eb17b68482aa7/1626108194743/what_is_stasis_in_rhetoric.pdf
    • https://static1.squarespace.com/static/60bf69b23f3791685666e32d/t/60e7e6ffd56f0f3612717eb3/1625810687730/72161987138.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b87c.bin
cd1c340034f9a6952e173be016d3364198d2e16723a3f6c4be90f14ff515b3e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xB87C 16584 bytes
font_01_sfnt_off0000e397.bin
dc1f3e1417ba9db8b095168572ed4470689563cc8668235032618c52f474e77a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE397 10776 bytes
font_02_sfnt_off0000fc63.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC63 16792 bytes