Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d1dad504f3c284d…

MALICIOUS

PDF

69.3 KB Created: 2021-09-17 23:32:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2952479226db05ee0b132e7c29d4b2ec SHA-1: 7096767144093cf2822f65f15c0c32768d72427a SHA-256: 4d1dad504f3c284d6db9abe73c21900635105d879e9c09655b41f982b9935d7e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised or disposable domains, indicating a link farm designed to lure users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

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 https://krisoc.ru/uplcv?utm_term=delete+history+for+android PDF link annotation
    • https://zmiz.hr/userfiles/file/terafewebiximavujugeviz.pdfIn PDF document text
    • https://tierlistei.ch/downloads/32637061485.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/nipuv.pdfIn PDF document text
    • https://inprovitcolombia.com/ckfinder/userfiles/files/wupuzegil.pdfIn PDF document text
    • https://thietbixanh.net/uploads/files/bofituvogimajiloxetoni.pdfIn PDF document text
    • http://munnarteabungalows.com/userfiles/file/rojipagad.pdfIn PDF document text
    • http://thegioimercedes.com/upload/files/4003933124.pdfIn PDF document text
    • https://npkfertilizerproduction.com/d/files/gufamin.pdfIn PDF document text
    • http://aktasmatbaacilik.com/resimlerfiles/manalawasigapikoxu.pdfIn PDF document text
    • https://rux-thai.com/ckfinder/userfiles/files/56495995833.pdfIn PDF document text
    • https://12shio4.com/contents/files/76591624597.pdfIn PDF document text
    • https://cahayaapi1.com/contents/files/supowawoverolevakigu.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/161429a7e2707a---38071246843.pdfIn PDF document text
    • http://bushurov.ru/images/files/94705398067.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/16141a2c57f189---pogafinoso.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/161316c920bdf4---nikofisibavoxuredazorej.pdfIn PDF document text
    • https://vicareyou.com/userfiles/file/35194615575.pdfIn PDF document text
    • https://somogyplusz.hu/files/92156301635.pdfIn PDF document text
    • http://pphjako.pl/userfiles/file/38992682324.pdfIn PDF document text
    • http://immobiliareborghi.com/userfiles/files/48434139222.pdfIn PDF document text
    • http://lactopad.com/uploads/files/25801464373.pdfIn PDF document text
    • https://retrofitoman.com/ckfinder/userfiles/files/46748257547.pdfIn PDF document text
    • http://globalsublimation.net/uploadfile/files/fiwuzotudim.pdfIn PDF document text
    • http://4darchitecture.org/img/all/rafiga.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_off0000b2c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2C9 14640 bytes
SHA-256: 008a89a67c2d3114c31fade499a875ddd29c38f50e9a177be08bd89cd3cdb315
font_01_sfnt_off0000d799.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD799 10568 bytes
SHA-256: 9ecdb9921c348ef57743f92f965af1fe5f9d479093ca2b46ee23069fb515e3a3
font_02_sfnt_off0000efae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFAE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1