Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bdd313c2a589130…

MALICIOUS

PDF

87.4 KB Created: 2021-09-03 18:30:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 15e764013c867dffae4746c40d836806 SHA-1: 8f9c4404819d44453f60a86031f663f28ad66e06 SHA-256: 5bdd313c2a5891307a465ba7f85ba2d9ac57932b22afbf5887ec4f2aba708290
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the structure and URL patterns suggest an attempt to lure users to external malicious resources, likely as part of a phishing or SEO poisoning campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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://tomaszfilipczak.pl/userfiles/file/84833523136.pdf In PDF document text
    • http://www.velkoobchod-man.eu/ckfinder/userfiles/files/19936578140.pdfIn PDF document text
    • https://ozanetiket.com/TasarimAcarnet/serhali/upload/files/1048897164.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/87623382145.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3a6c9f0482---gapovebosowipepikutoxin.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6c47aef71---lijabutanizimijo.pdfIn PDF document text
    • http://se-ty.ru/uploads/userfiles/file/85128697189.pdfIn PDF document text
    • http://kulturazebrak.cz/userfiles/kinefiguk.pdfIn PDF document text
    • http://studiogiovannone.com/userfiles/files/76774304622.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/zuwofinozoxebibexogomakuv.pdfIn PDF document text
    • https://artcer.ru/files/uploads/files/fedajizivatelobavo.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/tevk8red5ncsd63t4fberqp27q/likokiz.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/bd2237f5fd13fad81a37b083dfa7971f/vufokizuvebopudozuvatinol.pdfIn PDF document text
    • http://lasfyy.com/uploadfile/file/20210807004813318.pdfIn PDF document text
    • http://446888.top/userfiles/file/8583425199.pdfIn PDF document text
    • https://eurouniversal.eu/ckfinder/userfiles/files/lumokalu.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/88546865606.pdfIn PDF document text
    • http://gimhaejazz.com/fckeditor/userfiles/image/7547391900.pdfIn PDF document text
    • http://ballarioarchitetti.eu/userfiles/files/85403519123.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/kekomudafibaguriletawodu.pdfIn PDF document text
    • https://digireg.nz/upload/51773482283.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021080712135120.pdfIn PDF document text
    • https://lesura.net/userfiles/file/ludazul.pdfIn PDF document text
    • https://thefertilizergranulators.com/d/files/tevajifekitukavi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=manual+de+taller+piaggio+zip+50+2tPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1e50e2ecb---fugapox.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_off0000e9fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9FB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001020d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1020D 20088 bytes
SHA-256: 66d207a412567de465e14cc7619e3c77c5d99c984c18d2d19e879f8ca49b67a4
font_02_sfnt_off000136b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136B8 10928 bytes
SHA-256: 1ef6cad696b022e56143a6ea7bfd505862e6ac43c5fefb83685dfe32d37211ef