Malicious PDF — malware analysis report

Static analysis result for SHA-256 f24d6ea983d76668…

MALICIOUS

PDF

76.0 KB Created: 2021-09-23 00:44:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 05a4ed51b73e63666ea68f6f8e56f9a6 SHA-1: 7ff4824e2cd78f85ff563ac878285e0764d5d0c4 SHA-256: f24d6ea983d766687b736e16fadec86ce188a3d24d8b4e813c86ada73eca59fe
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it contains a link farm pointing to compromised WordPress upload storage and other potentially malicious URLs. The PDF structure and embedded links suggest it's used as a lure to redirect users to external, potentially malicious, content.

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://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613d61cf4a3b4---duvodesanorezuno.pdf In PDF document text
    • http://tv-sat.cz/userfiles/file/38634583789.pdfIn PDF document text
    • http://mcrlclient.gilcom.ro/ckfinder/userfiles/files/besexeje.pdfIn PDF document text
    • http://domadoma.cz/userfiles/file/14073310487.pdfIn PDF document text
    • https://harley.dataroom.tw/upload/files/29142684926.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/19152020244.pdfIn PDF document text
    • http://classtool.info/upload/files/74089778642.pdfIn PDF document text
    • http://www.gesas.it/media/mailinglist/file/vefagenudezumezitov.pdfIn PDF document text
    • https://bititechnika.com/uploads/file/95311821505.pdfIn PDF document text
    • https://glaskunstcentrum.nl/images/file/35764953931.pdfIn PDF document text
    • https://a-pointpro.com/cms/ckfinder/userfiles/files/wawoxagaduluxo.pdfIn PDF document text
    • https://www.nitdgp.ac.in/uploads/userfiles/files/87842290907.pdfIn PDF document text
    • http://studiotecnicoforace.eu/userfiles/files/zowefomexerobe.pdfIn PDF document text
    • https://poulinstrapscan.com/userfiles/file/kejezelunuwefeboxaribixim.pdfIn PDF document text
    • http://liily.jp/upload/file/20210905033031.pdfIn PDF document text
    • http://domplus.su/userfiles/files/mexapupusazigewemowabiwud.pdfIn PDF document text
    • https://vieclamday.com/userfiles/file/boralofawoz.pdfIn PDF document text
    • https://mondoaudio.it/img/uploaded/file/81963506553.pdfIn PDF document text
    • http://mottaing.eu/userfiles/files/sopitemod.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1612f98f41c1ba---31108136200.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/62319206102.pdfIn PDF document text
    • http://mediacast.vn/ckeditor/upload/files/16175374876.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132dd14c6cbb---fugekapomixikafadawig.pdfIn PDF document text
    • http://rheumatology.institute/upload/content/file/jisegelaja.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=how+do+you+block+a+text+message+on+androidPDF 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_off0000c2fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2FD 17616 bytes
SHA-256: b5e153d49b3a64e59848501cba37261c1cc407107d6ccb38cb171c08df8ec190
font_01_sfnt_off0000efe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE0 11340 bytes
SHA-256: 234047433494d1939363e3bb7323901539cfd55b27028474299bc3cb7ddccc26
font_02_sfnt_off00010a64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A64 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1