Malicious PDF — malware analysis report

Static analysis result for SHA-256 adcbfcaffd8f40e3…

MALICIOUS

PDF

72.8 KB Created: 2021-09-21 08:49:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 677563641f6940d32e3054fa645342db SHA-1: 437a3edc4bba07a43c50cf2d020fe77d88f9cfe0 SHA-256: adcbfcaffd8f40e31af73189051086e68fe16682c63bd66051b69eeebf52627c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics and the PDF_SEO_DISPOSABLE_LINK_FARM rule further support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://nomylo.ru/uplcv?utm_term=fall+guys+free+unblocked PDF link annotation
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/c3cbfce90c3413a3355a3bdff15bcdab/1797083063.pdfIn PDF document text
    • https://dolnoslaskialarmsmogowy.pl/imgturysta/files/xomofi.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/nuzegi.pdfIn PDF document text
    • http://terralis.net/catalogue_dynamique/file/dejotawazip.pdfIn PDF document text
    • http://location-venise.com/italie_documents/files/62680389623.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134b1220b9a0---66373618326.pdfIn PDF document text
    • http://uralinteh.com/uploads/files/73780515654.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210908013138752.pdfIn PDF document text
    • https://promobryansk.ru/userfiles/files/guvanasabizerakefaxozuv.pdfIn PDF document text
    • http://chenruichem.com/upload/files/titevojagisawidonip.pdfIn PDF document text
    • http://cpghollywood.com/userfiles/files/kipinevidajeparemivefe.pdfIn PDF document text
    • https://dichvuketoansg.com/luutru/files/9172502107.pdfIn PDF document text
    • http://wdnederland.nl/file/48006563764.pdfIn PDF document text
    • http://giayviettri.com/img-ftec/files/dekazefamofometaxoxar.pdfIn PDF document text
    • https://giorgiosantinelli.it/file/bakofutamutavopi.pdfIn PDF document text
    • http://yjsyrj.com/userfiles/file/46615150121.pdfIn PDF document text
    • http://dekoblickfang.de/userfiles/file/30557307545.pdfIn PDF document text
    • https://thediamangroup.com/_images/files/58674169284.pdfIn PDF document text
    • https://xn--psg-9lac.hu/files/files/nipujokumebovoxas.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/bebabunakasolidi.pdfIn PDF document text
    • https://futurefacesmiami.com/uploads/file/nazumero.pdfIn PDF document text
    • https://digireg.it/upload/ridakeveju.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161302784d1381---xanusadatolufewesogim.pdfIn PDF document text
    • http://ff-engineering.com/userfiles/files/japofovezuridimut.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_off0000bafc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAFC 10884 bytes
SHA-256: f8f408ea808b8d689ba1f31f75fb7f5b45c16a73f0295b226916a338b9cd6f40
font_01_sfnt_off0000d419.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD419 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ec2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC2B 16040 bytes
SHA-256: ef9c663a8c8f1af81ed39613761907e293d04fc539948f61526f2d2d47a77b8b