Malicious PDF — malware analysis report

Static analysis result for SHA-256 a35bca02041e6c42…

MALICIOUS

PDF

77.6 KB Created: 2021-09-21 08:50:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 31b5ccbd53c273b94223651b4129f739 SHA-1: 34b163346fa1800b16688320c17cef810cccbe8e SHA-256: a35bca02041e6c421104a73170f1fe4265351a76e9ee6ba922de5833cd7afe68
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links. The presence of 'utm_term_redirector=True' and links to compromised CMS uploads suggests a coordinated effort to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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 http://proxima-online.it/public/file/lanufetalezegolewesij.pdf In PDF document text
    • http://affordableadobe.com/ckfinder/userfiles/files/2901827364.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b246f0a565---52147875677.pdfIn PDF document text
    • http://sportsbettingconsultants.net/cote_dor_import/admin/ckfinder/userfiles/files/24518300370.pdfIn PDF document text
    • http://caytrong.vn/Images_upload/files/95566074011.pdfIn PDF document text
    • http://omatsuri.kr/data/userfiles/files/sopiverakujemuwalefil.pdfIn PDF document text
    • http://wronba.com/uploads/wysiwyg/file/68059835027.pdfIn PDF document text
    • https://austarpharma.com/upload/files/42713382387.pdfIn PDF document text
    • http://jinistudy.com/_UploadFile/Images/file/rigedezimexixu.pdfIn PDF document text
    • https://tainandentist.com/uploads/files/202109200042362806.pdfIn PDF document text
    • http://studioguagnoni.it/userfiles/files/zosise.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/f46297fe8ecc4a794201a184c3efa26b/93073774250.pdfIn PDF document text
    • https://self-storage.sg/images/uploadedimages/file/fobukoxipanap.pdfIn PDF document text
    • https://bor-diing.com/upload/files/72680718751.pdfIn PDF document text
    • http://erago.cidees.com/uploads/files/8383183636.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/ruxatagibinewidulokesa.pdfIn PDF document text
    • http://mrspk.com/ckfinder/userfiles/files/xiserumevuzejimodaximo.pdfIn PDF document text
    • https://danielfelber.ch/userfiles/file/24266326032.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/0e281ee685472d66097a19c0e59751e3/xutox.pdfIn PDF document text
    • http://mbfeed.vn/upload/files/45229393696.pdfIn PDF document text
    • http://flyingfish-stay.com/userfiles/file/88364989420.pdfIn PDF document text
    • http://siciny.eu/userfiles/file/26746920810.pdfIn PDF document text
    • http://www.shjkyq.com/up_files/FCK/file/60730923476.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b04ec21e8f---lowuxaxaderimegidajamato.pdfIn PDF document text
    • https://uslugiinzynierskie.eu/eurostyl/photos/file/nosetufutuvoguz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=sucide+squad+full+moviePDF 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_off0000c8d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8D9 10724 bytes
SHA-256: c7f78fe83e1f2e6567b42569a3fc37077b9ee09b739d8581bb61875dbf19c215
font_01_sfnt_off0000e147.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE147 18452 bytes
SHA-256: d5ef0e8c8d0b1e6d0fe60882c901d315cd6f89d2e296d69319cbb9035cb57bbd
font_02_sfnt_off0001111b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1111B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1