Malicious PDF — malware analysis report

Static analysis result for SHA-256 644524161628c17a…

MALICIOUS

PDF

73.9 KB Created: 2021-09-19 00:32:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 904eba119088180fc3da480e8746a45c SHA-1: ffd53db4e6c253f3795fafa3d90ac81dd791c742 SHA-256: 644524161628c17a42f746d2304e1025a77031b31ac5f3e56e29eba6ce3d1c5c
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm with numerous external URIs, suggesting a phishing or SEO manipulation scheme. The embedded URLs point to various domains hosting PDF files, reinforcing the link farm hypothesis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://grupopiscis.com/upload/files/15712401228.pdf In PDF document text
    • http://rentator.com/uploades/fckeditorfile/rumaxatizevu.pdfIn PDF document text
    • https://rewaqousha.net/userfiles/files/22716756585.pdfIn PDF document text
    • http://manpukulivermore.com/uploads/files/razixurolojenuva.pdfIn PDF document text
    • http://zafirkort.com/uploads/files/19828719102.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139a1544ed05---ratofif.pdfIn PDF document text
    • http://dgelc.com/userfiles/file/20210914153622.pdfIn PDF document text
    • https://tunhuaduytan.com/upload/userfiles/files/ratizolatokolo.pdfIn PDF document text
    • http://sovaimm.it/userfiles/files/tetume.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/sijuvulunopabovugi.pdfIn PDF document text
    • https://gionggiacam.gagiongvitgiong.com/ckfinder/userfiles/files/wofotawitovemenutovix.pdfIn PDF document text
    • http://jlsxjy.com/right/UploadFile/file///2021091118174173499.pdfIn PDF document text
    • http://logicamail.it/draft/media/libeviratojevade.pdfIn PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/jokogajaroxuvurekimaxajo.pdfIn PDF document text
    • http://www.oteliapelsin.ru/ckfinder/userfiles/files/72693523155.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/um0pqufn328ejvjh4s9tr9lv7u/texexigol.pdfIn PDF document text
    • http://jdjcnc.com/upfolder/e/files/20210906110217.pdfIn PDF document text
    • http://plenaseguroseprevidencia.com/fotosempresa/files/pojipapebitotusenozuz.pdfIn PDF document text
    • http://xinge168.com/uploads/files/20210904192136_159975.pdfIn PDF document text
    • http://internet-trade.eu/UserFiles/file/79323185056.pdfIn PDF document text
    • http://micruts.org/userfiles/file/21581868457.pdfIn PDF document text
    • https://tomas-music.com/contents/files/55316680646.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/88575185919.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/zalanozakorodim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=tv+channels+app+for+pcPDF link annotation
    • 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_off0000c080.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC080 10416 bytes
SHA-256: 8e2481e2b9b1b2aaf7d770641266575089fa061feb2171cb2b5eac3a9e23f565
font_01_sfnt_off0000d815.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD815 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f027.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF027 16396 bytes
SHA-256: 55f2a4e99620fef1645cb5266628d1d55462c301c53c50f2c73b146e9a93f306