Malicious PDF — malware analysis report

Static analysis result for SHA-256 756c943983413e28…

MALICIOUS

PDF

79.1 KB Created: 2021-09-15 13:54:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: adae9e75053e8265e82c48dd67c4330f SHA-1: 324a2a6601833ff1d52d70d12289740bc360486f SHA-256: 756c943983413e28afb064474834beda67e87ac3d544045b6343c0649faa9210
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users. While no scripts were explicitly extracted, the nature of the embedded URLs and the PDF structure strongly suggest a phishing or malware distribution vector, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://smidgel.ru/uplcv?utm_term=aplikasi+buat+desain+baju+di+android PDF link annotation
    • http://angarakshaksecurity.com/userfiles/file/72813294050.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/67153860690.pdfIn PDF document text
    • https://kcss.hu/korosi/userfiles/file/genugawujotujezisukevoke.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/161387d367b5b9---96056738929.pdfIn PDF document text
    • http://www.pavimentosyreformasferlu.es/ckfinder/userfiles/files/sobuval.pdfIn PDF document text
    • https://www.sesc-am.com.br/Selecao/ckfinder/files/motiwixolunaxamikifolas.pdfIn PDF document text
    • https://alwillislifecenter.org/ckfinder/userfiles/files/18241497110.pdfIn PDF document text
    • http://xn--h1aaebajlcgx.xn--p1ai/sadm_files/2812007146.pdfIn PDF document text
    • http://gdfsztal.com/uploadfile/files/ziwugodot.pdfIn PDF document text
    • https://gosselindesign.com/images/from_fckeditor/fichiers/8596937250.pdfIn PDF document text
    • https://anbuadidravidarmatrimony.com/ckfinder/userfiles/files/ribokuz.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/gudanipuwekife.pdfIn PDF document text
    • http://inphuduong.vn/upload/files/49744594688.pdfIn PDF document text
    • http://stfurnimart.com/file_media/file_image/file/vepojasivexogiwabad.pdfIn PDF document text
    • http://kronospan-mofa-hungary.hu/editor_up/30280891172.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161405066cb05f---60341567910.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161329861a1d49---76756430077.pdfIn PDF document text
    • http://fosterfreezesantarosa.com/uploads/files/82123552673.pdfIn PDF document text
    • http://bftt.marketsearching.com/upload/files/lukavegubizizopozaror.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/m1he24j4d6mjeei003r910chtu/14473055113.pdfIn PDF document text
    • http://www.ville-dammarie.com/ckfinder/userfiles/files/nulevegobisuxi.pdfIn PDF document text
    • http://tokyoto.pl/UserFiles/file/77296759873.pdfIn PDF document text
    • http://oumkua.com/userfiles/file/3945397341.pdfIn PDF document text
    • http://indagosrl.it/userfiles/files/698016989.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_off0000d470.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD470 10828 bytes
SHA-256: c78f7f9fe9c65d3ab2504185c39f767fe404c4f6f08bea28cc995c95b7780605
font_01_sfnt_off0000ed4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED4E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010560.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10560 15956 bytes
SHA-256: 448e742484b8400756433551c69063fa706112ccc002261fdbad753d9da6899f