Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8c03397838caf21…

MALICIOUS

PDF

72.1 KB Created: 2021-09-26 18:35:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 8e857fcbe51627a771a71995941859f0 SHA-1: 9aa0e2fe0a7b0364fa484b3db6f99568d0830727 SHA-256: f8c03397838caf21c44c2a574013cf7e88f56daafd7ee12eaeba5aadf9615c38
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious documents designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9902

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://medvor.ru/uplcv?utm_term=mini+militia+unlimited+health+hack+version+download PDF link annotation
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613af2568785b---patedapetetalepovososajeb.pdfIn PDF document text
    • http://tweedehandswikkelaar.nl/app/webroot/files/userfiles/files/98333648572.pdfIn PDF document text
    • https://szallas-karpatalja.net/upload/fabomasubu.pdfIn PDF document text
    • http://hieuchuan.com/upload/files/sojavozuziz.pdfIn PDF document text
    • http://yummyschool.com/_UploadFile/Images/file/pekududes.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16130685c94290---tulutomubadumu.pdfIn PDF document text
    • http://montpellier-businessplan.eu/mbp/upload/images/images/upload/ckfinder/6029750578.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/vikudepizibunakezuzadu.pdfIn PDF document text
    • http://centralgiving.com/media/userfiles/file/39466578445.pdfIn PDF document text
    • http://associazionemillesogni.it/userfiles/files/56209056937.pdfIn PDF document text
    • https://taiwan-tiaya.com/upload/tiaya_official/files/gasesoso.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/xebum.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614139e9c3348---63301413109.pdfIn PDF document text
    • http://vetcarefoundation.org/userfiles/file/fevelenosivuv.pdfIn PDF document text
    • https://rheinfurth.de/userfiles/file/xipunedubofitivomagerix.pdfIn PDF document text
    • http://starcity-vinhomes.vn/app/webroot/img/files/64363423804.pdfIn PDF document text
    • http://portalcom-b2b.es/img/user//file/_0838143001631700613.pdfIn PDF document text
    • http://showpalmedical.com/userfiles/tulanuposukusikotu.pdfIn PDF document text
    • https://letajicikoberce.cz/userfiles/file/tazozizatilapemababiv.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16148328e99f03---dipaj.pdfIn PDF document text
    • https://nedimgame.com/calisma2/files/uploads/zemitutazaja.pdfIn PDF document text
    • http://www.saveurspoitoucharentes.com/admin/ckfinder/userfiles/files/lunefujofuwajopalos.pdfIn PDF document text
    • https://dla-pracownika.pl/pliki_user/File/lepekefawisudob.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/19701811059.pdfIn PDF document text
    • http://indexone.ru/upload/file/bufusutumidenoxafar.pdfIn PDF document text
    • http://tofuyatogo.com/uploads/files/ginezosokufarefasogo.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_off0000b71a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB71A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cf2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF2C 16272 bytes
SHA-256: 715398c4089208821d7f13890ab76ad13a509a98e1d0df8543f814f4bf139e6e
font_02_sfnt_off0000f8cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8CC 10972 bytes
SHA-256: 5def996001e2c836e31d4d0b58a6c345c213e5792bf0dcfaf33c572eed7e4f25