Malicious PDF — malware analysis report

Static analysis result for SHA-256 50cc0b31d54055cf…

MALICIOUS

PDF

95.5 KB Created: 2021-07-25 14:11:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 5923040a62798d930f2401c2500679c3 SHA-1: 41631a1688567ec9d64093808c3c0756e21d6a46 SHA-256: 50cc0b31d54055cf86779a57473cafe7b67248b265db7b1522907f91ea4cc442
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan. It contains numerous embedded URLs, many pointing to compromised CMS upload storage or disposable hosting, characteristic of a link farm. The primary purpose appears to be directing users to external, potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 http://aire-limpio.com/img/editor/file/bagupumimatew.pdf In PDF document text
    • http://cocoal.com/uploads/file/20784881967.pdfIn PDF document text
    • http://change4best.ru/upload/file/76228795167.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/6784919309b1da0dafb1005c1ff40e7c/21153198870.pdfIn PDF document text
    • https://securitydm.eu/slicice/file/padeladavemu.pdfIn PDF document text
    • http://akgikorea.com/file_upload/fck_upfile/file/15349662974.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7522433726---36691691944.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16080b3a1570f7---lutizazosup.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160914bb28a5bc---69874685497.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/jdq3q5k7rmn1rn0k2bdcd57rj2/27094524073.pdfIn PDF document text
    • https://urbanlivin.lu/userfiles/files/jusatefulexibuzoku.pdfIn PDF document text
    • https://wipaphun.com/UserFiles/File/8791305544.pdfIn PDF document text
    • http://yaeram.com/userData/board/file/lanagemupesanatev.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/83947720439.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a413fc6ca07---47419522036.pdfIn PDF document text
    • http://griesvoegwerken.nl/UserFiles/file/nedosezi.pdfIn PDF document text
    • https://chameleoncoupons.com/adgprocessing/uploads/files/fonowadabodi.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd68c80df5a---63508542627.pdfIn PDF document text
    • https://atesolve.com/ckfinder/userfiles/files/88801468325.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1607330833c199---51601583993.pdfIn PDF document text
    • https://citytrafik.nu/images/file/36944355283.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/16087f90c50525---zozekubasuwofuweni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=avatar+musik+indonesia+mod+apk+1.0.1aPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_007_off00013058.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x13058 21132 bytes
SHA-256: 236a686116e1cb08e7c0ab31a4b5b5642c2470015ba45284c0478411e7092b7b
font_00_sfnt_off0000e7f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7F7 10988 bytes
SHA-256: fbee94a4c5021ccedf7272fcae663a9ff8c3933e72db01514e1f9a82cf5904fb
font_01_sfnt_off00010186.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10186 18004 bytes
SHA-256: 4e07055e867af3cad6ed84419f357c7334c2c7a8b646dcb1fe1ed861d22c37e3
font_03_sfnt_off00015507.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15507 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1