Malicious PDF — malware analysis report

Static analysis result for SHA-256 543a420cc756b11d…

MALICIOUS

PDF

81.6 KB Created: 2021-09-21 17:45:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0247022d8bfdc4793dc0d518bd1b4a93 SHA-1: 44c2f52faee6ad487c88b774e01eebef529c3b38 SHA-256: 543a420cc756b11d276fec9f95480a69e3115d607df79842104a60484e0a87b5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or trojan delivery. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crewmak.ru/uplcv?utm_term=movie+club+apk+download PDF link annotation
    • https://quanghuydulich.vn/img_duhoc/files/xofepasubelumuxubevujasi.pdfIn PDF document text
    • http://woodwork.pl/ubezpiecz/obrazy/file/kafuvetoboxotabewirujis.pdfIn PDF document text
    • https://fo-prefectures.com/pages/files/finukilesonewi.pdfIn PDF document text
    • http://eksternest.be/images/file/fejatulefawixodipifi.pdfIn PDF document text
    • http://avon-bratislava.sk/files/files/veligujali.pdfIn PDF document text
    • http://pumarecovery.com/userfiles/files/jovob.pdfIn PDF document text
    • http://tasarimak.com/ckfinder/userfiles/files/79906541309.pdfIn PDF document text
    • http://coyada.com/up_images/up_images/kuminisolibijaxibeg.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/dasisagipejopimibeboribo.pdfIn PDF document text
    • http://dirpub.org/editor/ckfinder/userfiles/files/55745685792.pdfIn PDF document text
    • http://www.macrolepidoptera.hu/userfiles/files/2772622492.pdfIn PDF document text
    • http://youil.org/userData/board/file/kavodegefujixanizaf.pdfIn PDF document text
    • https://propiedades.net/ckfinder/userfiles/files/84099623007.pdfIn PDF document text
    • https://www.ruchya.com.tw/upload/files/noriv.pdfIn PDF document text
    • https://lotte-ppta.net/beta/assets/file/68512703057.pdfIn PDF document text
    • http://xn----7sbabaajmdfbk3ddf3azka3b6a2r.xn--p1ai/ckfinder/userfiles/files/91631309510.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fac6c58af0---69000899454.pdfIn PDF document text
    • https://dewalt-naradi.cz/media/upload/editor/file/jogisimakafagujubiki.pdfIn PDF document text
    • https://crcnueva.naturasoftware.com/uploads/images/files/78295787247.pdfIn PDF document text
    • http://nj-rshb.com/v15/Upload/file/2021913529209397.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1612fbda3c89bd---43567129680.pdfIn PDF document text
    • http://mylodge-naoshima.com/images/blog/file/voluwigonenuforuwokupid.pdfIn PDF document text
    • http://yogaschoolofkerala.com/photos/editor/files/fejal.pdfIn PDF document text
    • http://nwatchonline.info/userfiles/file/mirox.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_off0000dae3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE3 17664 bytes
SHA-256: 1a607da29f3c201bfeee99a0d79e028782264023017a352a0be650eb1f87231c
font_01_sfnt_off00010846.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10846 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001205d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1205D 10616 bytes
SHA-256: 15455217cc2e0e999ce74086db16c9b3b114c931195d40947b935d39cc0ea6d6