Malicious PDF — malware analysis report

Static analysis result for SHA-256 11616a33a9c99f99…

MALICIOUS

PDF

79.9 KB Created: 2021-09-13 00:01:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: af2f243d76b488f274303fe8d226b6de SHA-1: cd096cf7f18443d744bc9131c504e9cf879d4b19 SHA-256: 11616a33a9c99f99a761737720657dcae2864d2fa1c47b9bcdfc5ffd94d27a31
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, many of which point to disposable hosting or compromised WordPress sites, suggesting a link farm designed to distribute malicious content. The presence of a 'download button' heuristic further supports the lure-based attack pattern. ClamAV detection and ML classification confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://krisoc.ru/uplcv?utm_term=pokemon+x+and+y+gba+file+download PDF link annotation
    • http://shatalarab-llc.net/userfiles/files/xitulojofozetakij.pdfIn PDF document text
    • http://paraleumarian.ro/app/webroot/files/userfiles/files/40278207341.pdfIn PDF document text
    • https://groupunsur4.com/contents/files/taxasozajerizex.pdfIn PDF document text
    • http://elhammagazine.com/ckfinder/userfiles/files/mokuruwi.pdfIn PDF document text
    • http://maurovalleferroarchitetto.eu/userfiles/files/danoveranugitilosar.pdfIn PDF document text
    • http://hftyby.com/upload_fck/file/2021-9-10/20210910033728242908.pdfIn PDF document text
    • https://apra.pl/files/file/83478401368.pdfIn PDF document text
    • https://cauthinh.com/luutru/files/45136056595.pdfIn PDF document text
    • http://charivne.info/images/file/18781131331.pdfIn PDF document text
    • http://gabinetortodontyczny.eu/userfiles/file/vuseviw.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/fosenexakuxowebivew.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/8862b798208e8f11418a7dee616897db/99429776184.pdfIn PDF document text
    • https://groupburuemas1.com/contents/files/jezivezuzavex.pdfIn PDF document text
    • https://theloneranger.tv/clients/loneranger/ckfinder/userfiles/files/dikifivemomowimonuvidi.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/89058558638.pdfIn PDF document text
    • http://traktor-tv.de/sites/default/files/file/vugowoworonemosebiwoxu.pdfIn PDF document text
    • http://refah4ter.info/basefile/hotelrefah4terir/files/vuxunafisorurunekidisite.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/jpot7bd2ft2or2cie0ui7sn6mf/64553907991.pdfIn PDF document text
    • http://railwaysrailroads.com/upload_files/files/ximekuwu.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612f21ca0c027---52045239779.pdfIn PDF document text
    • https://n-vv.dk/userfiles/file/lozometiketulabus.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210904_120916.pdfIn PDF document text
    • http://kapsalonvogue.nl/files/file/zijovazunawewirufet.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613430c678d3c---14427513628.pdfIn PDF document text
    • https://www.bmo-agencement.fr/ckfinder/userfiles/files/laxaduvep.pdfIn PDF document text
    • https://www.tamilsaga.com/ckfinder/userfiles/files/jaseg.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_off0000d20a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD20A 10868 bytes
SHA-256: 9be6f7102a7dab1938c223126ae6700df82118dc639b8fc5520a9defca965a6e
font_01_sfnt_off0000eaf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001030a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1030A 17904 bytes
SHA-256: 930ffb9e96cd2174229b05e248bcd468f85e4dffdfa856edc4c9b6512a5d6e9d