Malicious PDF — malware analysis report

Static analysis result for SHA-256 31447d916ee76190…

MALICIOUS

PDF

72.0 KB Created: 2021-09-17 14:38:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c0e4ea2a02bd467c13b147f335dfd78b SHA-1: 8ba3fb161a473bf5272630d1d853248775367f59 SHA-256: 31447d916ee76190f8836dbed8fad004f7682d19cda97f1961b830d0d30a9ada
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest a phishing or trojan payload is intended. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://chcial.ru/uplcv?utm_term=prince+of+persia+the+forgotten+sands+mobile+game+download PDF link annotation
    • http://opuspoint.com/ckfinder/userfiles/files/97400195882.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/2097685055.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/318a45d738ea2f83822be6c95dfb48ec/21480515724.pdfIn PDF document text
    • https://actsonics.com/uploads/files/202109061108286941.pdfIn PDF document text
    • https://jss-moms.si/upload/File/gadadevotofulaxubevij.pdfIn PDF document text
    • https://yifff.se/userfiles/file/gawogezibagunofomagejej.pdfIn PDF document text
    • http://romanasulcikova.cz/userfiles/bujamugode.pdfIn PDF document text
    • https://semot.com/Store/userfiles/file/25426790957.pdfIn PDF document text
    • http://kennycojewelry.com/userfiles/files/202109/1631837267.pdfIn PDF document text
    • https://tagoproperties.com/ckfinder/userfiles/files/9924318005.pdfIn PDF document text
    • http://sellmysayarah.com/userfiles/files/jegoketozomurevulipijikar.pdfIn PDF document text
    • http://akiisushi.com/uploads/files/63427604565.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/a68ed4eda2f8eccd53eabc9736b522ba/limarakujiwufezabagipeb.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/5320010782.pdfIn PDF document text
    • http://biondiairsystem.it/userfiles/files/15991038838.pdfIn PDF document text
    • https://handientu.vn/userfiles/file/59641828068.pdfIn PDF document text
    • https://dunaweb.co/bg_image/files/dotivot.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143446415e4b---dipukiwidutererazuza.pdfIn PDF document text
    • http://vanprodukt.cz/UserFiles/File/puwutinesedubot.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/1614071026184d---lubukukilubope.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137fcc472b23---fidux.pdfIn PDF document text
    • http://timnhanhonline.vn/upload/files/49159876748.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/19689367411.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_off0000b9c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9C4 14992 bytes
SHA-256: b0121dded8b4d400fb1d558058242dc0c272121040505e7d54b9099b14ffd1f1
font_01_sfnt_off0000dfdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFDB 11292 bytes
SHA-256: 98b19e428b1fdd641acddacd80bf9bfe897ed7b6667b0aad449d732f9ef12d8b
font_02_sfnt_off0000f9cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1