Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb826a944f1e8af6…

MALICIOUS

PDF

76.6 KB Created: 2021-09-05 08:19:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a8937d8ad6400189d23120b3785338e2 SHA-1: fca3014669e13c2348a17f0b8eabbeed72fe2c36 SHA-256: fb826a944f1e8af6d9275b4305796f4254abac1a6eb60c3f87a7279dbe1ff5b9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external URIs, many pointing to compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and numerous URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for further actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 https://ketchas.ru/uplcv?utm_term=math+placement+test+pdf PDF link annotation
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/puxunaxurafi.pdfIn PDF document text
    • https://carlojans.com/cms/file/nosoparukukuribon.pdfIn PDF document text
    • https://agencement-menuiserie-var.fr/stockages/files/butazuzefolelizezexa.pdfIn PDF document text
    • https://agroadvanced.com/app/webroot/newsletters/editor/files/18888336462.pdfIn PDF document text
    • https://bibliotheque.ville.deux-montagnes.qc.ca/ckfinder/userfiles/files/45013996904.pdfIn PDF document text
    • http://consade.com/userfiles/file/297180040.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/pqmpvd7ploh1nruam7hppaosk4/66676658707.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c05616e7dd9---24398669510.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160d62194d7450---bejewimevapijaxexuw.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/102adeaf536a4d557b434f04498a6ad7/fufolixagidar.pdfIn PDF document text
    • http://youandisagenix.com/ckfinder/userfiles/files/94524443638.pdfIn PDF document text
    • http://simp-q.ru/userfiles/file/xipezeburefetosugoselen.pdfIn PDF document text
    • http://odpadykj.cz/UserFiles/File/kagubawemenajapetaga.pdfIn PDF document text
    • https://aep-tc.com/cache/fck_files/file/gabomejip.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608068d784360---pazutiwowomew.pdfIn PDF document text
    • http://xn--sanitrprofi-p8a.ch/fckeditor/editor/images/file/94609884209.pdfIn PDF document text
    • http://mobilenmr.com/files/files/vazanax.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1610616dc95b97---nudiboxugotovabezux.pdfIn PDF document text
    • http://pytextiles.com/userfiles/file/23403199028.pdfIn PDF document text
    • http://brandiassociati.it/userfiles/file/vedopaneluxun.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/nidalisaroxazowen.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/12d6559d2593b847ef3a1cb5a71a8b88/53451723398.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/ktf68iin9tt2cqi4jf2rc9da2v/71108637193.pdfIn PDF document text
    • http://maysoi.com/hinhanh_fckeditor/file/600790693.pdfIn PDF document text
    • https://sofupingame.com/calisma2/files/uploads/39292365971.pdfIn PDF document text
    • http://abwmarlboropike.com/uploads/files/32571202017.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_off0000c9f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9F0 10564 bytes
SHA-256: cd2c3f6bb23b9033fac1e604b3d8769338a3e6c585e8bcbae5cbe6d1724c80f9
font_01_sfnt_off0000e1de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1DE 16728 bytes
SHA-256: 4bca9244630184eab5a96f5c3073c752ecd8b551aea7b08f5ce34906e85e5bc5
font_02_sfnt_off00010ce6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1