Malicious PDF — malware analysis report

Static analysis result for SHA-256 b36e83d284d5fbfd…

MALICIOUS

PDF

80.8 KB Created: 2021-09-08 21:01:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4ccf3bf3f3d45d1eb9ab4142481ad9ca SHA-1: 5c77476405f0d99e44cbb028ff332afeef2da144 SHA-256: b36e83d284d5fbfd33c8ab8fc9b50f7742928efc7babb10d23849c5bba58ff0b
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate the PDF contains a link farm, with several URLs pointing to compromised CMS uploads or disposable hosting, suggesting an attempt to lure users to malicious sites. The presence of numerous unknown URLs further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://holocaustresearch.pl/nowy/photo/file/74878076889.pdf In PDF document text
    • http://pscworld.eu/ckfinder/userfiles/files/8668565287.pdfIn PDF document text
    • http://emilygrilltogo.com/uploads/files/sobafutem.pdfIn PDF document text
    • https://selapro.com.au/application/third_party/ckfinder/userfiles/files/47365843459.pdfIn PDF document text
    • https://centrumschoolka.pl/photos/file/raxofositaj.pdfIn PDF document text
    • http://olimpic.hu/ckfinder/userfiles/files/tomulubul.pdfIn PDF document text
    • https://ketex.com/trcgp/ckfinder/userfiles/files/80120937068.pdfIn PDF document text
    • https://dondepodemosir.com/userfiles/file/34479347295.pdfIn PDF document text
    • http://coyada.com/up_images/up_images/4863463585.pdfIn PDF document text
    • http://kmbb.at/userfiles/file/lefosu.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/4b118af82da781a43e1979a478469704/kabezarojiwumelojevola.pdfIn PDF document text
    • https://nsaimmigration.com/userfiles/file/kejomabaxesidupaz.pdfIn PDF document text
    • http://maekalocal.com/Maeka/UserFiles/File/14014421328.pdfIn PDF document text
    • http://iscelenie.info/files/file/97818857915.pdfIn PDF document text
    • http://ukwoodrecycling.com/userfiles/files/56370945009.pdfIn PDF document text
    • https://xn--23-6kci4asohe8k.xn--p1ai/userfiles/file/dibabixejixiforoto.pdfIn PDF document text
    • http://munnartourism.com/uploads/file/sisepijajavetatitu.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161316c2a71f2c---notafozulutufo.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16133d09016775---36707516694.pdfIn PDF document text
    • http://xn--2e0b95unoa536adofm5h.com/userfiles/file/75193668631.pdfIn PDF document text
    • https://satnamunicipalcorporation.com/admin/ckfinder/userfiles/files/90413238755.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/risejokoxegewunolu.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135a6333ddb5---bobamibavibulesabovobib.pdfIn PDF document text
    • http://chhattisgarhsanskritboard.in/sharpinstitute/images/files/22356891804.pdfIn PDF document text
    • https://www.prshots.com/ckfinder/userfiles/files/78668410219.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=celery+tutorial+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_off0000d886.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD886 10464 bytes
SHA-256: bdbd79506cb2486ac3b001a38e2e9b2f2cfce03d82702ea329c95b2a24ed6f89
font_01_sfnt_off0000f070.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF070 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10882 17492 bytes
SHA-256: 5b50042eb8e8b6c16148cb437fe0156436674cb46f3dd00384ba159aa0b1f30f