Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bc8bcde308d2979…

MALICIOUS

PDF

82.5 KB Created: 2021-09-17 17:03:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e5c77ae6065366c0db87773c87facbec SHA-1: 7d6391b58f5293c348361ab0efd1a4f2e6f1378a SHA-256: 4bc8bcde308d29792782f696ee4412afbb2f948549d1ffaefdedd0c80348d63e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs and is flagged as a link farm on disposable hosting, suggesting it's designed to redirect users to potentially harmful sites. While no scripts were explicitly extracted, the PDF structure and embedded URIs point towards a phishing or malware distribution vector, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://camphacement.vn/upload/files/75968248203.pdf In PDF document text
    • http://chiangmaicharmingtravel.com/ckfinder/userfiles/files/pasevilopuruwowumuzu.pdfIn PDF document text
    • http://xn--9i1b14lwsg1seumdzsx.com/upload/fckeditor/file/zukisagevimugu.pdfIn PDF document text
    • https://www.profiemg.cz/upload/ck/files/zigulekubukesu.pdfIn PDF document text
    • http://ipsaix.com/ckeditor/ckfinder/userfiles/files/76983315139.pdfIn PDF document text
    • https://goooinggroup.com/userfiles/files/20210905_195331.pdfIn PDF document text
    • http://www.shjkyq.com/up_files/FCK/file/tabonudeluje.pdfIn PDF document text
    • http://scvumaichiramen.com/uploads/files/kipalidafirafebas.pdfIn PDF document text
    • http://oldmotorsclub.com/files/file/68502729165.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/73894935294.pdfIn PDF document text
    • http://chromavials.com/d/files/rewurejarafozipisor.pdfIn PDF document text
    • http://boissee.fr/userfiles/file/97271872739.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/60990580373.pdfIn PDF document text
    • http://stellarvvv.ru/ckfinder/userfiles/files/bonasawiwif.pdfIn PDF document text
    • http://cn-junsheng.com/upload/file///202191101115871.pdfIn PDF document text
    • http://rockycheng.com/ckfinder/userfiles/files/dibagagigubonudenap.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/vugutisubedakixatokelite.pdfIn PDF document text
    • http://guerrazzi.info/userfiles/files/57152441528.pdfIn PDF document text
    • http://bienbao.org/uploads/files/80413768571.pdfIn PDF document text
    • http://kronikarp.pl/ckfinder/userfiles/files/65979609310.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134cbd025628---tobufofisofi.pdfIn PDF document text
    • http://wimborst-ceramics.nl/public/view/upload/fckeditor_images/file/42984137984.pdfIn PDF document text
    • https://essaidafm.com/uploads/FCK_files/file/81113267548.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/jebagofadepep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=robbery+bob+2+hack+mod+apkPDF 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_off0000ddd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f5e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E7 17472 bytes
SHA-256: 1eb12c48bd83eabfd5df5b59be8d369d598b766c9a57c21d4b84a6204ff4759a
font_02_sfnt_off00012376.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12376 10784 bytes
SHA-256: d8c5605378ea2e7a883af878fc1859de83f1a66d3cd25789b0a7e91354a64988