Malicious PDF — malware analysis report

Static analysis result for SHA-256 5af8511b1bc0237d…

MALICIOUS

PDF

70.1 KB Created: 2021-09-07 13:18:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 170ae8416ca6af3e6cf84a2a0bb23e2e SHA-1: 1503ea0b4a0aa72073cd52ec3c96ea849f53d507 SHA-256: 5af8511b1bc0237d52410c04401a7cdbde98b8762794540fcdc20977023fbbb6
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress sites, suggesting a phishing or malware distribution scheme. The presence of a link farm and the use of disposable hosting further support this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160acaecd53184---78520250020.pdf In PDF document text
    • http://doubletroubels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606dfaea8cdb1---bamugusigezelije.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070967e53274---wuvuveverolizivuxujexel.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a7627f3604c---gokofifokawex.pdfIn PDF document text
    • http://talentfuturesservices.com/sharpinstitute/images/files/30734119677.pdfIn PDF document text
    • http://easthighclassof1962.com/clients/2/24/240b89ecbeded73b1ae3fdc7544f4fd7/File/3104223816.pdfIn PDF document text
    • http://clinicaveterinariamontecchia.com/userfiles/files/56099956994.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/d0137795fc7a34a4dcdef031a972341f/26476149586.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/40086754639.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/j0rb7o1pkvnml95jv8b1899mui/98928308577.pdfIn PDF document text
    • http://aostavet.it/userfiles/files/43244715085.pdfIn PDF document text
    • https://istanbularicilikfestivali.com/upload/ckfinder/files/vinepisoganeregikiwawav.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b08068e42a3---gugidisejavisawowe.pdfIn PDF document text
    • http://www.psychophonie-tarbes.com/ckfinder/userfiles/files/kajeg.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/76733055519.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610d2326be6cc---kawinofirusedesotodefi.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/18014275508.pdfIn PDF document text
    • https://e-ceramika.pl/userfiles/file/goloworufetitefegonoset.pdfIn PDF document text
    • https://ltgtrends.com/wp-content/plugins/super-forms/uploads/php/files/bf0bed29b054593e72e330bfdb7a2aad/81470470829.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098678b04b2f---jugediwopexafitewefofuxov.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608f6ed3c0ab0---81538625834.pdfIn PDF document text
    • http://biswasi.com/userfiles/files/gadamokamokizi.pdfIn PDF document text
    • http://foodchemsino.com/d/files/wobavujidizeza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=organometallics+reactions+pdfPDF 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_off0000b464.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB464 14764 bytes
SHA-256: 74892966d5a72f80ab2d11403d9733379333ce70db89641f893eb02654faa0c1
font_01_sfnt_off0000d986.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD986 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f19d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF19D 10988 bytes
SHA-256: c07110b71beecf3df2a8224861a8274d02e1de9cb710ff57fecbcec7ea85a4c1