Malicious PDF — malware analysis report

Static analysis result for SHA-256 bff164a02b560b59…

MALICIOUS

PDF

73.5 KB Created: 2021-09-26 02:28:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 34c4183fb2557f2cf0a0d1e21d1b3cf5 SHA-1: c9f9d727291e6a0690c6f5ed797a6243aaa8b1b8 SHA-256: bff164a02b560b5969f5963655d582ecbd8248dab1cc44bc7b2b4bf1d8ca4016
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous domains, many of which are associated with compromised CMS uploads or disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the links and the PDF structure are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://cmorshomecareassociates.org/uploaded_files/userfiles/files/42888155852.pdf
    • http://nhagiatxanh.com/public/default/ckeditor/files/japulusutodo.pdf
    • http://dorapeyzaj.com/userfiles/file/68592320657.pdf
    • http://www.swiftsecurehosting.com/rsnpromotion/siteuploads/editorimg/file/mazitivagujur.pdf
    • http://glassick.com/userfiles/file/bokanerutosuwaposoxegakiw.pdf
    • https://specializzati.tecnaevolution.it/dataload/ckupload/33565287661.pdf
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161339af53b2c2---74722971700.pdf
    • http://vagtteam.com/userfiles/Files/17876736936.pdf
    • http://xn----7sbakif2a3azdub.xn--p1ai/admin/ckfinder/userfiles/files/48205835402.pdf
    • http://officinedesign.it/userfiles/files/nutesarezopemomi.pdf
    • http://xn--80aap0abfiql8h.xn--p1ai/admin/ckfinder/userfiles/files/75629489667.pdf
    • http://mamaskitchenorder.com/uploads/files/vumerowidixalijodawulef.pdf
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/4092cb59705e424e32cab6f1c669c195/87531613954.pdf
    • http://nickels.design/ckfinder/userfiles/files/27752687145.pdf
    • https://nazrabilisim.com/calisma2/files/uploads/39494322341.pdf
    • http://lanaecoloridabruzzo.it/userfiles/file/19282047590.pdf
    • http://zhongjiukeji.com/upload_fck/file/2021-9-9/20210909060429556542.pdf
    • https://portoggitter.no/content/files/userfiles/file///zisedomupupimotasuwufa.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/16143ce14e3c35---87305922830.pdf
    • http://archiw.gbpopatowiec.pl/img/upload/files/67586441490.pdf
    • http://pusheng168.com/uploadfiles/20210912103607.pdf
    • http://xz-brand.com/ckfinder/userfiles/files/lilup.pdf
    • http://savvyais.com/userfiles/file/bowobevebaxujunarid.pdf
    • http://baldonimarcostudio.eu/userfiles/files/jojosaku.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=xiaomi+a2+lite+stock+rom
    • 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_off0000b779.bin
53c56876adee138558873918fe074e1a79eea68b5fc54351a3e989d790616721
pdf-font-stream PDF embedded font (sfnt) at offset 0xB779 18440 bytes
font_01_sfnt_off0000e6ad.bin
a5b85edfa2a673a0f309b41f0ef3500c9d3983ad0432cd8ffef8e83892708457
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6AD 10504 bytes
font_02_sfnt_off0000feb1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEB1 16792 bytes