Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9b0ac4d80e7da79…

MALICIOUS

PDF

76.1 KB Created: 2021-07-14 02:44:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 90814d0fc2613cf51ed65f490531fe93 SHA-1: 265afb808fb430afff58811b6f4f80c0f316ba10 SHA-256: a9b0ac4d80e7da794631c68339957eab91fafb3bfa1c684c50b05845812a1f37
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to lure users to malicious destinations. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a malicious document, potentially leveraging JavaScript for further actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://krisoc.ru/uplcv?utm_term=if+teresa%27s+daughter+is+my+daughter%27s+mother+what+am+i+to+teresa
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/54e73fa3f1bc1d21d4fc6d1905577269/95401725998.pdf
    • http://zrdb-drogbud.pl/Upload/file/6884370358.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d15fd48ba2---miwokezalisawazemejetaf.pdf
    • https://fnb-concepts.com/images/uploads/files/texuk.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160aa985f38cbf---porepidasagakuvalew.pdf
    • https://tecnibat.net/uploads/archivos/zimegowarotob.pdf
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606d40be25e81---gupipuvu.pdf
    • https://lienlacanien.com/img_pages/file/21659603125.pdf
    • http://baybayankaauamo.com/clients/c/c9/c9e0f772d4a556598cfa564a27137582/File/11666504485.pdf
    • http://health-bridge.in/upload/file/losekuxik.pdf
    • https://pametnidom.hr/pametne_kuce/userfiles/file/53238194585.pdf
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d34505ebb6---ninezaw.pdf
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/577dfb58a578c53afc931995208c4229/fijixovenigovigabifekog.pdf
    • http://miroslaws.com/ckfinder/userfiles/files/xikuderola.pdf
    • https://heatingboiler.ca/fck_upload/file/panoz.pdf
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/ab4acb0ad19c1ab27fed9560b8ffba58/62981303413.pdf
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/72rgjvfjbo7mepbbmeurpae1u4/womepazajikubewuw.pdf
    • http://colorfulmedia.de/fotki/fotki/file/ragijezosusexotinixopug.pdf
    • http://codemessaging.net/ckfinder/userfiles/files/xenetekonunusotixor.pdf
    • http://poltinik.ru/userfiles/file/35326913826.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160744c0ac4314---96473693073.pdf
    • http://cottoneauto.it/userfiles/files/32551801710.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e36e80c1c2---xifolamogepof.pdf
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/o8vlc6ferca708os6caqdb7kur/35001115184.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_off0000c338.bin
b4934f34bf79b7f13f4865b6fca941653e4814a2946c6be98a0819a4fb951b9d
pdf-font-stream PDF embedded font (sfnt) at offset 0xC338 17764 bytes
font_01_sfnt_off0000f111.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF111 16792 bytes
font_02_sfnt_off00010928.bin
59c19fa9f98c8e59f38801952c38e73efc5098d9b95aabe3b51a3e544af702a4
pdf-font-stream PDF embedded font (sfnt) at offset 0x10928 10936 bytes