Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac36fc35c3dba628…

MALICIOUS

PDF

69.9 KB Created: 2021-09-30 16:08:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 37a984b12a06810b80c18a591720ef18 SHA-1: d638e503f10fb0cf501ea776a4a347dcddf048ae SHA-256: ac36fc35c3dba628ae90bee3c12cf1ee898cfd2d730fc04bf316d9e8e1075db5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was identified as malicious by ClamAV and an ML classifier. It contains a link farm pointing to multiple compromised WordPress sites and disposable hosting domains, suggesting an attempt to distribute malicious content or engage in phishing. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate effort to create a network of links for potentially malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://ctsgroups.asia/images/file/45907697180.pdf In PDF document text
    • https://pvcmikser.com/upload/files/30794714683.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/ef32e95c6137535fc8627a2868b8ffb5/mewurubuvaxularovabuvuzav.pdfIn PDF document text
    • https://journalofcritique.com/ckdosyalari/upload/files/janadajavixew.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/217739808a3183e84fc8f888b610a403/27538455505.pdfIn PDF document text
    • http://pomocnaukowa.net/Upload/file/vozux.pdfIn PDF document text
    • http://csc-0411.com/userfiles/file/20210905171835_p57h69.pdfIn PDF document text
    • https://www.disbel.es/ckfinder/userfiles/files/92482262274.pdfIn PDF document text
    • http://machulski.com/public/file/88366451518.pdfIn PDF document text
    • https://suruburi.net/mm/file/30090004502.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/takukesodajujojaruwoji.pdfIn PDF document text
    • http://spprp.pl/userfiles/file/tafapobevawitelodoz.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/selokewefepifizagunifama.pdfIn PDF document text
    • http://www.aamuhsv-madisonalumni.org/files/files/38348310026.pdfIn PDF document text
    • http://it-hair.com/userfiles/30464198891.pdfIn PDF document text
    • http://controldellaves.com/app/webroot/arxius/file/27056821208.pdfIn PDF document text
    • http://monteconsultants.com/image/upload/File/kobagasovulirogufo.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/72755138448.pdfIn PDF document text
    • http://arcenevents.nl/site/upload/files/gulekinanebok.pdfIn PDF document text
    • http://cistenivytahu.cz/upload/file/79032171686.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134aea9967c9---lafatarisafadudag.pdfIn PDF document text
    • http://maiodi.com/userfiles/files/66307498347.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/13561216183.pdfIn PDF document text
    • http://rosniyom.com/userfiles/files/8703005901.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=body+sore+from+workoutPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b297.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB297 10556 bytes
SHA-256: 744e468835c94cf1b7cd241afae834703ebe07fc21171cc9fd7dc75e3e0287fa
font_01_sfnt_off0000cad5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAD5 15316 bytes
SHA-256: 90972894b1e412883d411c8efbf0332bb4e3955df9e2e7293e5f6dc3debb3a0b
font_02_sfnt_off0000f1e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1