Malicious PDF — malware analysis report

Static analysis result for SHA-256 b358c385fa8949bc…

MALICIOUS

PDF

80.8 KB Created: 2021-09-16 18:22:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 904597f1d4c2e424a072d06c4ab0b14c SHA-1: 1f99e628a3d866c173c2218a1fcd3cb84e22a991 SHA-256: b358c385fa8949bce680d4c56e5683ec237fb87363d0d5b603685a4aae2d7094
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to potentially compromised CMS upload directories or are hosted on disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the PDF structure itself is used to host a large number of redirect links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://gemcom.org/userfiles/file/75429338812.pdf In PDF document text
    • http://kuryakyn.ru/userfiles/file/91664884331.pdfIn PDF document text
    • http://hongsung114.com/files/fckeditor/file/tamulekotemudalitezu.pdfIn PDF document text
    • https://tidurmalam2.com/contents/files/poxupo.pdfIn PDF document text
    • http://studiolegaletrotta.eu/userfiles/files/67804570194.pdfIn PDF document text
    • http://twilaw.com/files/files/15396887217.pdfIn PDF document text
    • http://ashokarefrigeration.com/userfiles/file/23304906186.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/fgd0ulfu34v9q9caveufvvs596/65109066940.pdfIn PDF document text
    • http://idrogastermoclima.it/Utentifile/FCKPage/file/pejurujifefiselu.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/desuvoferesajinakoxevo.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/8ddjurssqcp1dc8gnvm6ndpapd/3464023414.pdfIn PDF document text
    • https://olivermilk.vn/tctt/sites/aaa/file/39348308355.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ec11746be2---52179126476.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161435bbbf1b48---wutatipikavap.pdfIn PDF document text
    • http://dxqzx.com/ckfinder/userfiles/files/20210903_075622.pdfIn PDF document text
    • http://clingac.es/d/files/gafofefutukupi.pdfIn PDF document text
    • https://almuhja.com/ckfinder/userfiles/files/30844551533.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161419fc0a3a45---15861542046.pdfIn PDF document text
    • http://solarexperten.ch/fckeditor/editor/images/file/xarajujo.pdfIn PDF document text
    • https://traffictkt.com/viking1/uploads/files/padugujavigagesesuzo.pdfIn PDF document text
    • https://lacausedeslivres.com/userfiles/file/68730824065.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/52402351290.pdfIn PDF document text
    • https://corianderedmonton.com/ckfinder/userfiles/files/dufusumasegizititoke.pdfIn PDF document text
    • https://partetesal.ir/data/file/95409966862.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=oggy+runner+game+downloadPDF 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_off0000da0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA0B 16976 bytes
SHA-256: b0e0de656fd1bc92e09f0b6d4fa7049f58ed3e18a189788c2c778994a7868fd1
font_01_sfnt_off0001060c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1060C 10556 bytes
SHA-256: fb97fd442d176c122030ed964e47f70729ca212e4fa70629299b09a4937e5345
font_02_sfnt_off00011df9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DF9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1