Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1cbd00a96b9625f…

MALICIOUS

PDF

81.4 KB Created: 2021-09-21 22:52:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 52bda069764fb1d217df3877ba32c337 SHA-1: e16c4d87638a03c5cf9a87fb1ad619453dc4cbba SHA-256: b1cbd00a96b9625f9e2df0f33ab54ba52f26c4724caaf53dd23f77c901049d5e
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The presence of external URIs and link farm characteristics strongly supports a malicious attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://pistant.ru/uplcv?utm_term=como+activar+el+teclado+android PDF link annotation
    • http://privateeducation.sg/verzsape/demo/upload/admin/files/pusiduzovuk.pdfIn PDF document text
    • http://doo-san.com/userfiles/file/20210913172348.pdfIn PDF document text
    • http://naphogacomposite.com/upload/files/robekene.pdfIn PDF document text
    • https://klcconsulting.eu/klc/file/10937789169.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/161401d6cb161e---zupanujorakekowetege.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613510efe3989---3874357364.pdfIn PDF document text
    • http://tnslib.tools/userfiles/files/mogifiroxuxami.pdfIn PDF document text
    • http://nb-magnet.com/upload/files/23300878477.pdfIn PDF document text
    • http://baoveantam.info/upload/files/85992314087.pdfIn PDF document text
    • http://dc-07b6a75bc4d0.breakthrough-physical-therapy.com/userfiles/files/rududisebozofetaposejoji.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2f530b4fc---netiwusinenar.pdfIn PDF document text
    • http://thibangoto.com/app/webroot/uploads/files/25604964313.pdfIn PDF document text
    • http://4darchitecture.org/img/all/63955354622.pdfIn PDF document text
    • https://petrovsky14.ru/docs/files/xobejilatafarutesokiwub.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/zuvoxudolesi.pdfIn PDF document text
    • http://khmim.com/ckfinder/userfiles/files/jesidafukivezetajuzubejif.pdfIn PDF document text
    • http://yearbookplus.com/uploads/ckfinder/files/gejaluzedowopanakam.pdfIn PDF document text
    • http://sinproval.it/userfiles/files/20884423109.pdfIn PDF document text
    • https://tasleemdubai.com/userfiles/files/gekozekalaka.pdfIn PDF document text
    • http://hockjoohin.com/admin/uploads/file/zunemobajapaxa.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/mamijudalo.pdfIn PDF document text
    • https://airbays.com/userfiles/file/24518181715.pdfIn PDF document text
    • http://cadelupo.it/userfiles/files/22826129688.pdfIn PDF document text
    • https://itscebu.com/upload/file/20210905233334.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_off0000d6c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eedd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEDD 10460 bytes
SHA-256: 236fbf2ed6532dd9c1095a46bda10ce9cf15382146b2c85b6cab63953b4a3b92
font_02_sfnt_off0001069e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1069E 19360 bytes
SHA-256: bf93a7aa8c96ecf294fdc9a217de10d3e3b04ec74f522631ee09ad1ce01836e2