Malicious PDF — malware analysis report

Static analysis result for SHA-256 41445ed4a67e4206…

MALICIOUS

PDF

83.1 KB Created: 2021-09-23 00:09:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 2df9c0b82fd4b6160d5f5bb1382c5cad SHA-1: fd90393e0118fd64fe8132f39bfb673f294a21db SHA-256: 41445ed4a67e4206d6b8e3edfce5c9cfcfc579830e8b14c44f26ed39e77eed1a
104 Risk Score

Malware Insights

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

The ML classifier strongly indicated maliciousness, supported by heuristics identifying the PDF as a link farm pointing to compromised WordPress uploads and disposable hosting. The presence of external URIs and a call-to-action button lure suggests an attempt to direct the user to malicious content. No scripts were extracted, limiting the analysis of specific execution methods.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://medvor.ru/uplcv?utm_term=android+to+pc+calls PDF link annotation
    • http://modra-skola.cz/userfiles/file/dabobobajodozimurudovisen.pdfIn PDF document text
    • http://makesrealsense.com/ckfinder/userfiles/files/7445000065.pdfIn PDF document text
    • http://goldendazzle.com/upload/quangtri/files/49844155375.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161327d54d26e0---maxawagiku.pdfIn PDF document text
    • http://amidoux-peintures.com/ckfinder/userfiles/files/73846307725.pdfIn PDF document text
    • http://dalieuht.com/app/webroot/uploads/files/49583834183.pdfIn PDF document text
    • http://trust-law-firm.com/userfiles/file/20210911142932_506116834.pdfIn PDF document text
    • http://xn--80aafjbawrcdgsodbdciig4a5v.xn--p1ai/pict/file/98763606927.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/18b2eb5b06d989182238450485e456ab/lukoligididivudupeguxe.pdfIn PDF document text
    • https://leuphuotcamap.com/uploads/image/files/fifaxunowiwudeti.pdfIn PDF document text
    • https://napraforgohotel.hu/upload/file/luralejesewatutebuv.pdfIn PDF document text
    • http://www.s4b.nl/upload/files/78692039308.pdfIn PDF document text
    • http://daiichilogistics.com/uploads/news_file/4536399961.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16136f54d40f97---goret.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/1298985828.pdfIn PDF document text
    • http://szintai.hu/ckfinder/userfiles/files/tegabesugimedeneti.pdfIn PDF document text
    • http://grandp.ru/userfiles/file/84090976273.pdfIn PDF document text
    • https://taiwan-tiaya.com/upload/tiaya_official/files/47210264602.pdfIn PDF document text
    • http://topstec.com/d/files/54726628537.pdfIn PDF document text
    • https://delaneyllc.com/ckfinder/userfiles/files/68324799826.pdfIn PDF document text
    • https://eirai.org/editor/ckfinder/userfiles/files/78413959423.pdfIn PDF document text
    • https://euroquimicadistribucion.com/zabaleta/data/imagenes_contenidos/file/86720828081.pdfIn PDF document text
    • http://luxmeterthai.com/ckfinder/userfiles/files/nepakevijotiv.pdfIn PDF document text
    • http://e1pl2.nazwa.pl/busy/fotki/file/80635315982.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_off0000e0ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f8c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8C4 10356 bytes
SHA-256: 7106d42edee8d0c543c7cd1f7ebc1a331ab2e0504c68fb0a00c862514e2c767b
font_02_sfnt_off0001103e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1103E 18208 bytes
SHA-256: 88cd238a10b5f1001a4c5557bad7bc93ac3303ec4104cea160d1cbc58e061247