Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c0e00b752ee7956…

MALICIOUS

PDF

82.0 KB Created: 2021-09-17 23:01:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f66e910232f4fafc06a4f748b595a758 SHA-1: f879d279f2fa96c0011a4543ad88e6185bf5b2fa SHA-256: 9c0e00b752ee79568103b28b4af49e234470c1ffe829150a9bf58c4571c0eb62
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating malicious intent, including random and SEO-disposable link farms pointing to external PDF files. The ClamAV detection and ML classifier strongly suggest malicious content. While no scripts were explicitly extracted, the presence of numerous external links suggests the PDF is designed to redirect users to potentially harmful sites, likely as part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://rsti.biz/files/fck/file/18640956310.pdf
    • https://g55net.com/webpagebuilder/ckfinder/userfiles/files/zivopamuguvodozetegat.pdf
    • https://huanghecables.com/d/files/80481562834.pdf
    • https://songod.vn/uploads/image/files/19372568625.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/161396b71dc151---79476534633.pdf
    • https://bengalroys.com/ckfinder/userfiles/files/59391280614.pdf
    • https://ofly.om-digitalsolutions.cn/upload/files/28697739400.pdf
    • http://fzsvybbs.at/userfiles/file/soporedesoganovumizij.pdf
    • http://tlumacz-bialystok.pl/pliki/file/givobosupaxaloxi.pdf
    • http://cungcapbaoduongcuanhatban.com/upload/files/xibogiro.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d6bc35b69c---teramoroziroguxerigupiza.pdf
    • http://adance0112.com/upfile/editor/file/papap.pdf
    • http://gadkowski.pl/repository/filemanager/file/ravupexomavadafepanezuka.pdf
    • http://jl-vacuum.com/upload/files/wanevogebubid.pdf
    • https://sensesgrouphk.com/louis/STARKGROUP/ckfinder/userfiles/files/biwumamazilu.pdf
    • http://automsystem.com/UploadFile/file/20210902204343481.pdf
    • http://veterinarioassociatopacinidallatorre.eu/userfiles/files/65271745999.pdf
    • https://kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/85808497916.pdf
    • http://travelci.ru/ckfinder/userfiles/files/74090253286.pdf
    • https://mrdak.cc/uploadfile/files/74182420486.pdf
    • http://caphegiabao.com/upload/fck/file/62847315003.pdf
    • http://kondicionery-lobnya.ru/upload_picture/file/75717804752.pdf
    • http://tid.vn/upload/files/72203885860.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1613d03d19fbfd---jozaxexomarisumukasixamu.pdf
    • http://321eastern-thailand.com/userfiles/files/63453827545.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=coomeet+premium+mod
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/0d599e0dddfb7fba7b3faa3dd050985a/rexisomanasuju.pdf
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db74.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB74 16792 bytes
font_01_sfnt_off0000f386.bin
330dfbd4436edf7d6aa0e8ebe58da853abab6ba7e3cef765e7c458d0e3df22ba
pdf-font-stream PDF embedded font (sfnt) at offset 0xF386 18524 bytes
font_02_sfnt_off0001239a.bin
9c1ec311d5b52c651fcaabcc84458f44757c312943d7155d0e15a8f589167e25
pdf-font-stream PDF embedded font (sfnt) at offset 0x1239A 10204 bytes