Malicious PDF — malware analysis report

Static analysis result for SHA-256 bbd524d85843e0a1…

MALICIOUS

PDF

70.5 KB Created: 2021-05-24 20:12:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 14955d2df26a5fd653d9ff39a27cc156 SHA-1: 448694e7d0c87b6b528be429119e072b3d432996 SHA-256: bbd524d85843e0a11547ef8df9f8b92db9610fd3ca6442a675cbabcb5e26809f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

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 websites and disposable hosting, suggesting it's part of a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to be a lure related to employee warnings, which is a common tactic for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/g6greqe1onb4j732o548d9kna4/71282434159.pdf
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3bae8bd6e---72423627954.pdf
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/8fa368a102c078b6cd648af4e2084ac1/41306194568.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f7c09a4941---tusarokeg.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076592db0e9a---52313533286.pdf
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/ssp95e3u0stlit266vca1jdug6/43847855631.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/28c94ed21495f71d42a9111a33a209d4/zejumituzademadovagofosal.pdf
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/48sk0k3rv1fuk14vlus6lvgt8i/pumitepofusuzu.pdf
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/j14ht46jevtrv8lpegpfh8ftt0/kakonuboxijebolodigifujoz.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a060dd438b---xunipatasabit.pdf
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/e1cac857359873a0e409b1a489cbfc20/70631309676.pdf
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/da4f55df1763214c797b30a6dcc31898/riridefizipeli.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/74050d17c7fb95977bb681cc1a798f40/1181751873.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/738d5ab7482ac90190bfea965b51ae63/23985184548.pdf
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/192qib2oc955hnj8ooo8j5lk87/6924104962.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093a05b6305d---rixur.pdf
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/d8f7c3569b8b71d9403c27c00d62763b/filedilugupajejoxeros.pdf
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608320c7a2bcb---9072705171.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071b28e513b1---18725626072.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160971ad6c6f27---tedofogos.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=how+to+write+a+warning+letter+to+an+employee+for+insubordination
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d784.bin
74372f2420a9cc8b0ec73ada63b30d18aa43cafc33fb11c7c921d80f00345932
pdf-font-stream PDF embedded font (sfnt) at offset 0xD784 5656 bytes
font_01_sfnt_off0000eabe.bin
decf15265e9f39ed5386fc2774f7a497109b325d81b786c3dadf4a808b22b01c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEABE 9708 bytes