Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1936ae81048748f…

MALICIOUS

PDF

76.4 KB Created: 2021-09-19 17:42:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a08b6acf91898ad278c8dc9b98c9d669 SHA-1: a4fd278baecc15020f7c3e4d49a275e57ffd552d SHA-256: a1936ae81048748ffc50d3dc878e905d1c6f78782d007f68d39e5d47b9a4ee0f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and is identified as a link farm, with many links pointing to disposable hosting or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://chcial.ru/uplcv?utm_term=gospel+song+thank+you+lord PDF link annotation
    • http://bakefruit.com/uploads/files/202109060322393004.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/16146649400320---taxaxebedanizuku.pdfIn PDF document text
    • http://smartcirclegroup.com/userfiles/file/nuwuwabexumafa.pdfIn PDF document text
    • https://clifestyle.net/uploades/userfiles/file/18994681444.pdfIn PDF document text
    • http://iscelenie.info/files/file/najekukebipexuloradaw.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/3586744229.pdfIn PDF document text
    • http://colegiosantarosa.com/uploads/imagem/file/xulatatamigunenisol.pdfIn PDF document text
    • https://www.pepinieres-gey.fr/ckfinder/userfiles/files/pifezisenejafo.pdfIn PDF document text
    • https://hotelmitrutarija.com/uploaded/files/57564683436.pdfIn PDF document text
    • http://xn--5dbfbdrd7azav1bcx.com/sites/default/files/file/dapedax.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec805000e7---pefimigimotirol.pdfIn PDF document text
    • http://hondaotohaiphong.vn/upload/files/1887588384.pdfIn PDF document text
    • http://elrey-uslugi.ru/media/file/dujovuwafa.pdfIn PDF document text
    • http://playoz.com/ckfinder/userfiles/files/temubelonaxokunefamol.pdfIn PDF document text
    • http://fge-service.com/userfiles/file/koneturipusalumufa.pdfIn PDF document text
    • https://xn--lenachatka-57b.pl/uploaded/file/xefurenozoruza.pdfIn PDF document text
    • https://otterdisplay.com/userfiles/file/lojexivawaxibonazemoxeve.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/1613af89c2c3ff---jopeladadegukes.pdfIn PDF document text
    • http://esebtekstil.com/resimler/files/1843437357.pdfIn PDF document text
    • http://alltimescare.com/attachment/files/latimuwafafo.pdfIn PDF document text
    • https://groupekheidri.com/ckfinder/userfiles/files/tutumomazifot.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613682c29c106---35436717182.pdfIn PDF document text
    • http://hairfibers24.com/upload/file/gawam.pdfIn PDF document text
    • https://jiu-hang.com/upfiles/editor/files/57927560412.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_off0000c533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC533 10924 bytes
SHA-256: f2651e1edbc4b2df7b7d13c78e9aae70817a74b8eff4205bbd6015f352a22522
font_01_sfnt_off0000de5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE5B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f66d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF66D 17624 bytes
SHA-256: 9428952297a812aad606494caa05fb176a4f433e553624a2fbd25231ff047d5d