Malicious PDF — malware analysis report

Static analysis result for SHA-256 f773951c10d251ac…

MALICIOUS

PDF

74.7 KB Created: 2021-09-06 11:59:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b66e6fbdf2257c909b780f364e58dff8 SHA-1: 20235cbd5946f3645bd12ab36de7da5a2b5794b6 SHA-256: f773951c10d251acabef71ae6aa2471ca188a5a2051b992819e3691819decc01
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to compromised or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as a phishing trojan. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://irlanc.ru/uplcv?utm_term=hippias+major+plato+pdf PDF link annotation
    • http://df-2.de/images/daten/file/7415720758.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071970438db8---narofob.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/zitowamoxolububagivenuj.pdfIn PDF document text
    • https://bahceneryaman.net/public/content-images/files/51110899716.pdfIn PDF document text
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/fee3cea99fc37ea04f682aa0d83c39f5/jazejo.pdfIn PDF document text
    • http://thessalonikiflights.com/files/files/tofoxokixanofuxaxalok.pdfIn PDF document text
    • http://sztarmedia.hu/_user/file/sexenusutiba.pdfIn PDF document text
    • http://varosom.hu/userfiles/files/96391900001.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160adc811c1e4b---rumigisenosajugakubif.pdfIn PDF document text
    • https://kfk-dekoration.dk/images/uploadedimages/file/68750446781.pdfIn PDF document text
    • http://riskhedgetech.com/uploaded/file/99300313160ab8c2dcbd58.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/f1710f3b88bfd61b26b25ad13db21466/55610887572.pdfIn PDF document text
    • http://sakuragiramenandsushi.com/uploads/files/87659826571.pdfIn PDF document text
    • http://washchienluoc.com/upload/file/21213048322.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/24047683876.pdfIn PDF document text
    • https://n-v-v.dk/userfiles/file/bepogivitugenotamugave.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/zutetujajem.pdfIn PDF document text
    • http://midel.me/userfiles/file/zogusib.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/xozexuvatatidof.pdfIn PDF document text
    • http://nawooelcs.com/upload/userfiles/2021/07/files/210704200144.pdfIn PDF document text
    • http://bijverhoeven.nl/uploads/files/64604251063.pdfIn PDF document text
    • http://equipociclistaugeraga.com/ciclistas/userfiles/file/72561306030.pdfIn PDF document text
    • 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_off0000be33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE33 18116 bytes
SHA-256: 3d002db6be0e087cb454642bdf9b1d1f09cda06f6675f102c6580f70c796d529
font_01_sfnt_off0000ed27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED27 10544 bytes
SHA-256: 0e282922d437159fd7f0a14002ba091de300d6d89279c069eb5f0ab5f57380f6
font_02_sfnt_off00010517.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10517 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1