Malicious PDF — malware analysis report

Static analysis result for SHA-256 2fe56f3570223be5…

MALICIOUS

PDF

75.5 KB Created: 2021-09-21 18:29:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 96aac6c7123e5729b19a3ec4660197e9 SHA-1: 2d4bb2f64642ff56d7e6b1483fe50e27ae5a9449 SHA-256: 2fe56f3570223be53eb04f3db7ba76fbbea6c74a8e8e75c28587d3dec1a3222a
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document identified as malicious by an ML classifier. It contains numerous embedded URLs that point to various PDF files hosted on different domains, many of which appear to be compromised WordPress sites or use disposable hosting. This behavior is consistent with a link farm or SEO spam campaign, potentially used to distribute further malicious content or manipulate search engine results. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 5

  • 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://northcoteplaza.com/userfiles/file/fijufafowiferuk.pdf In PDF document text
    • http://myslizdrave.com/soubory/xerevovalele.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/pg9odch6u9vlnl9938k47ba331/39159505680.pdfIn PDF document text
    • http://elosc.com/upFile/file///ITX202109202259226155.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131512ebac2b---mawesofadurajapezojas.pdfIn PDF document text
    • https://chezgregoire.fr/userfiles/zonubolinafaravewovuku.pdfIn PDF document text
    • http://szpk.hu/_user/file/vuxovudutapoxiwimi.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/25f0c73e0f97cad173b5eebcd74560e0/55800716527.pdfIn PDF document text
    • http://casavacanzesanvito.eu/userfiles/files/36082967500.pdfIn PDF document text
    • https://artedelvalle.cl/gal/files/file/77179216973.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/161327c05bd981---29421666309.pdfIn PDF document text
    • http://michardardillier.com/ckfinder/userfiles/files/1725569020.pdfIn PDF document text
    • https://norservis.cz/files/files/xezafovozozavufiwuxuguku.pdfIn PDF document text
    • http://www.farimar.pt/imgs/uploads/40687415991.pdfIn PDF document text
    • http://www.ezmoving.com/file/dawuluzotajisepodegixod.pdfIn PDF document text
    • http://qdsenfeng.com/data/files/48030639782.pdfIn PDF document text
    • https://megashina24.ru/files/files/73983049491.pdfIn PDF document text
    • http://www.hkimm.hk/_bin/ckfinder/userfiles/files/9369797967.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb5e207ef7---60400957718.pdfIn PDF document text
    • http://www.taxivanclass.com/uploads/ckfinder/files/lukobejaxeletagebigamidu.pdfIn PDF document text
    • http://lgassociates.in/uploads/57981183860.pdfIn PDF document text
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/91313408252.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=decompile+androidmanifest+xmlPDF link annotation
    • 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_off0000c3e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3E1 10884 bytes
SHA-256: 666cd862aaef310224d553bff315678480ac8aa5d0e04a228c221ff5ac90eade
font_01_sfnt_off0000dd03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD03 16676 bytes
SHA-256: 658299c5490833ca88eaba70c5644581ac2b1112629084d04fd5fefad9f91cd7
font_02_sfnt_off00010837.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10837 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1