Malicious PDF — malware analysis report

Static analysis result for SHA-256 21a66565be627c88…

MALICIOUS

PDF

80.5 KB Created: 2021-09-20 21:10:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2b682754ebb3d7fe2914c1826722fa96 SHA-1: 3208a7eb4bf84c6d5d746f2ecbc84ce7b44e3deb SHA-256: 21a66565be627c8882ddd832153f8bfad3eb9ece091eaee520a43f890e200ac7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports the nature of the attack, which involves directing users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://irlanc.ru/uplcv?utm_term=how+to+clear+temporary+files+in+web+browser PDF link annotation
    • http://paolacaone.eu/userfiles/files/87234117935.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/e5c19635884685889e6d2dbbbcd72f29/tenegewupoxagovopukamizo.pdfIn PDF document text
    • http://www.bongbansaigon.com/uploads/files/78638745255.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/64822811081.pdfIn PDF document text
    • http://gazetavk.ru/img/file/34647450869.pdfIn PDF document text
    • https://lotteppta.net/beta/assets/file/titigexagalimelitapagosor.pdfIn PDF document text
    • https://bakwanudang.com/contents/files/60630565283.pdfIn PDF document text
    • http://architettomontanino.eu/userfiles/files/35246633172.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/299ac13babe001187ea6ab3e0b9427a2/49105662758.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/4944c40d5a5c97146fa728b484a9757a/82160015669.pdfIn PDF document text
    • http://skomi.ru/img/files/file/dadadopalavegujisowonunoz.pdfIn PDF document text
    • http://bodybybodyology.com/ckfinder/userfiles/files/42520777095.pdfIn PDF document text
    • https://blnk.eu/userfiles/files/89946550625.pdfIn PDF document text
    • http://m-s-g.ru/userfiles/files/lojiwi.pdfIn PDF document text
    • http://itagqatar.zajeltel.com/itag/file/files/34472930411.pdfIn PDF document text
    • http://asavn.vn/uploads/userfiles/files/limuketewi.pdfIn PDF document text
    • http://xingzhongjing.com/userfiles/file/20210902131329_1122921028.pdfIn PDF document text
    • https://jmbarrenetxea.soinuenea.eus/files/galeria/files/runurojetenusijipe.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/89987006347.pdfIn PDF document text
    • http://khamtribacninh.com/images/files/60942673601.pdfIn PDF document text
    • https://at1-turbo-j3t.com/contents/files/56454535893.pdfIn PDF document text
    • http://tutek.eu/userfiles/file/93200722622.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/9520c149d95b9b31effa171df07d0636/48665550675.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_off0000d70d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD70D 16780 bytes
SHA-256: abb780ad7d4288e8f7e9e23db5e3f1c4976dbbe584b44830945633f673cae430
font_01_sfnt_off00010271.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10271 10972 bytes
SHA-256: a09ae9293a00c7483d240087ee2b2a06471fa3224a700af5ed2e04482499411b
font_02_sfnt_off00011bbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1