Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7a877516d1cbb4f…

MALICIOUS

PDF

75.9 KB Created: 2021-09-16 23:52:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e351fb5b46ca84488857163f9a0cc1e7 SHA-1: d5cb0232aaebb38d25ae933b87b9492bf3ea61e4 SHA-256: b7a877516d1cbb4f3acc130794cefda58e56ec5fb730ab92c643b35d2b881b79
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs that form a link farm, with several pointing to compromised WordPress upload directories. The primary purpose appears to be redirecting users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://crewmak.ru/uplcv?utm_term=nfs+no+limits+android+cheats PDF link annotation
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ed17bef35---garewovamepidive.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea03a83df0---xididopufo.pdfIn PDF document text
    • http://disonde.com/filespath/files/20210905221015.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/78004180.pdfIn PDF document text
    • http://tinavaron.com/ckfinder/userfiles/files/1178699280.pdfIn PDF document text
    • http://location-appartement-venise.com/italie_documents/files/52258319667.pdfIn PDF document text
    • https://protrialse.eu/files/files/finosijewoxawag.pdfIn PDF document text
    • http://fullerton.kopanramen.com/uploads/files/mosuradetunurofidogutixe.pdfIn PDF document text
    • https://euronet.stonavka.cz/webpagebuilder/ckfinder/userfiles/files/3620321702.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/16139b3e9db4d2---fakerofofapaginumubu.pdfIn PDF document text
    • http://bbpcosmetics.com/admin/upFiles/2021-9/file/56110592799.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/k1894q38i3afeh41vu9lgah2l6/32606592420.pdfIn PDF document text
    • http://24hnbc.com/assets/ckfinder/core/connector/php/uploads/files/nezibi.pdfIn PDF document text
    • http://519pf.com/userfiles/files/42117893698.pdfIn PDF document text
    • http://technimexvn.com/images/ckeditor/files/xogakezo.pdfIn PDF document text
    • https://shen-su.eu/gfx/userfiles/files/kesulexafabiretuzunegize.pdfIn PDF document text
    • https://it-remarketing.pl/app/webroot/media/files/50012622926.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/81311140062.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/bigavomalutez.pdfIn PDF document text
    • http://lotusburbank.com/uploads/files/1243561525.pdfIn PDF document text
    • http://mellorymotors.ru/admin/ckfinder/userfiles/files/50315012995.pdfIn PDF document text
    • http://kieryk.pl/img/userfiles/file/mafivaza.pdfIn PDF document text
    • http://sportsbettingconsultants.net/cote_dor_import/admin/ckfinder/userfiles/files/89778541706.pdfIn PDF document text
    • http://tucholainfo.pl/userfiles/file/67942523234.pdfIn PDF document text
    • http://studiotecnicoforace.eu/userfiles/files/pirilomevasugonagunusiw.pdfIn PDF document text
    • https://rt9.rspo.org/ckfinder/userfiles/files/bolipodubewobirubup.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_off0000c22b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC22B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA3D 18092 bytes
SHA-256: 75c8108f77429aa2a3457dfe2101c0832c5a23bc5c1a393b02e3f87ca78f1445
font_02_sfnt_off000109b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109B0 10716 bytes
SHA-256: 6a562d818d37ee5cfe3d0e8bfae0b1915c66682bf94389008e7f16e91b7abfe0