Malicious PDF — malware analysis report

Static analysis result for SHA-256 c10d881ce86e7657…

MALICIOUS

PDF

97.5 KB Created: 2021-07-25 09:37:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: c32c3c4bc479346f474bd1df73f31c33 SHA-1: 7c45f1ef4a40db50edc760d064487d53381858b4 SHA-256: c10d881ce86e76570a05ad2c20eff33f1e1c0bd960400bb385c5510618af44e5
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS platforms. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of numerous links suggests an attempt to redirect users to malicious sites for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://havanic.com/cache/fck_files/file/jemexexapibarimodekofa.pdf In PDF document text
    • http://allamericannursing.com/userfiles/file/83705668700.pdfIn PDF document text
    • http://cnex.cc/images/blog//file/mikepesirinojavidagebixez.pdfIn PDF document text
    • http://patroha.hu/file/kelipuw.pdfIn PDF document text
    • http://nuestrasenoranm.org/clients/8/88/88a18899c67a61641ca1f7d027daa919/File/xenigidapepodewatazowu.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/mirov.pdfIn PDF document text
    • https://discovery99.com/userfiles/file/70863382499.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/1770275feb17f7050156f775c6722d79/rilufipi.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/6jjmteq3l8hf82cm0selhubto2/legodamuravutejaj.pdfIn PDF document text
    • http://cwesp.biz/upload/file/gugabe.pdfIn PDF document text
    • https://olterus.info/contents//files/tixudizolezele.pdfIn PDF document text
    • http://remaining-mc.de/userfiles/file/88695416001.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/ugkqdr0daafa02g7vh5mmgs1l3/xevijaserebadi.pdfIn PDF document text
    • http://taiwan-casters.com/userfiles/file/26302690685.pdfIn PDF document text
    • http://wccflooring.com/userfiles/files/47584575539.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/f1dde83e0defafff77dab8e355e6c8ef/14503559257.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/c57d2a820d42669943e1c319bdfaa8f3/17091700570.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/48583605332.pdfIn PDF document text
    • http://www.proyecpapel.es/ckfinder/userfiles/files/48675446852.pdfIn PDF document text
    • http://nieruchomosci-swidnica.pl/userfiles/file/28686975074.pdfIn PDF document text
    • https://avonsteel.com/UserFiles/file/nelisogabug.pdfIn PDF document text
    • http://cadeco.com/testingsites/advantage_aviation/assets/media/file/xabebutomok.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d6e5073aa1---musaluku.pdfIn PDF document text
    • http://ottotech.center/userfiles/file/79409240589.pdfIn PDF document text
    • http://vtvxm.vn/userfiles/file/levabavimukajuredukajok.pdfIn PDF document text
    • http://mgocsm.in/userfiles/file/vajex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=bac+blanc+maths+terminale+stlPDF 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
font_00_sfnt_off0000fbfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBFD 10568 bytes
SHA-256: fe947547b8879be68aae54b576f6c403b2c31f2d62d90fc2e3b26cc9b6b24ae9
font_01_sfnt_off000113eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012bfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BFC 16756 bytes
SHA-256: 027b4fcc0c630321d05b12cc8d939ac31782af36f65f93f52bb5d46033962716
font_03_sfnt_off000143c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143C8 19320 bytes
SHA-256: 88b160cebcc46887eb8d94e082046f050adae58a4d7928770c5b9866eec289ae