Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab57d859d2a575e3…

MALICIOUS

PDF

74.6 KB Created: 2021-09-08 14:47:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 1631e48713e045ced9fd738daa3dfb10 SHA-1: ccc58857ad4abf84a21b1e13f9dde084b9dcf046 SHA-256: ab57d859d2a575e34cd942e746aaba127f08e06416c0f59c9de071c92e701773
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The document contains numerous links to external websites, many of which are hosted on compromised CMS uploads or disposable domains, suggesting a phishing or malware distribution campaign. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, indicating the document is designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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=save+pdf+as+read+only+without+password PDF link annotation
    • http://littlepearlbooks.in/data/eimages/file/kuxezunidanevidate.pdfIn PDF document text
    • http://carneslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xezawi.pdfIn PDF document text
    • http://harmonie-avion.fr/actualite/files/nexega.pdfIn PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/xawaniguxedijinezawad.pdfIn PDF document text
    • https://www.indoorclub-informa.com/boletines/img/file/47809779819.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/9qlsupgrhjq643aohs3i8core2/28499031002.pdfIn PDF document text
    • http://twfbs.com/ckfinder/userfiles/files/xexanexapuxolugujinivefi.pdfIn PDF document text
    • http://igabana.com/upfolder/e/files/20210905180856.pdfIn PDF document text
    • https://libertyrealestate.in/ckfinder/userfiles/files/24043634165.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/2628c34c0f06845826a0957c28be42b2/zezemobukarogudew.pdfIn PDF document text
    • http://ziconiavip.com/uploadfck/file/89382140802.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/vodaxegubonuzako.pdfIn PDF document text
    • http://twtime.com/uploads/files/202109072044573595.pdfIn PDF document text
    • https://thic.net/plugin/ce1/ckfinder/userfiles/files/xezevimogivimuvimago.pdfIn PDF document text
    • http://candientushinko.com/images/file/zegunojowixe.pdfIn PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/duxazapamaterebogoxi.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f22fe2666b---sixunivewijejezo.pdfIn PDF document text
    • http://saveursetsavoirs.fr/image/file/73375126833.pdfIn PDF document text
    • http://topp.pl/_topp/file/xosedonevodopusupamigujez.pdfIn PDF document text
    • http://markone-tools.com/upload/files/xadobi.pdfIn PDF document text
    • http://feg.vn/uploads/files/76082350650.pdfIn PDF document text
    • http://aodaiminhhanh.com/app/webroot/uploads/files/36894425252.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_off0000bc26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC26 18268 bytes
SHA-256: 2147677e54531ff1a5ac9feb51790a6db5f9a915445614faa186c69470683bfd
font_01_sfnt_off0000eb2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB2B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010342.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10342 11036 bytes
SHA-256: 3cd1841a98ec45c52a3075f008433c636d2c5cc8e2d2dbd2b9874939fd85890c