Malicious PDF — malware analysis report

Static analysis result for SHA-256 a20457f338f8ed33…

MALICIOUS

PDF

81.7 KB Created: 2021-09-18 06:51:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 3e9125ffac810c8e149a5f141de5fe57 SHA-1: e0253e4fdc8b0b3ca15890cb2d8f514ab20b1cd1 SHA-256: a20457f338f8ed33d63794274b7f80d8dfdcf83ee16d9028cbc4ae0bb978ef1b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external domains, suggesting a phishing or malware distribution scheme. The PDF structure and the presence of external links are consistent with spearphishing attachments used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 https://wastran.ru/uplcv?utm_term=stop+ads+apk PDF link annotation
    • http://gnox.vn/upload/files/7105185518.pdfIn PDF document text
    • https://fallahi-sch.com/userfiles/file/figopasolitibamevusa.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613eeb4179bb5---salusedesasar.pdfIn PDF document text
    • http://expnavi.com/sites/all/sites/default/files/file/valanalepifebov.pdfIn PDF document text
    • http://focalthai.com/file_media/file_image/file/87195438021.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161384efb8bfb9---ruxiginipigo.pdfIn PDF document text
    • http://aqua4you.hu/userfiles/file/6584783384.pdfIn PDF document text
    • http://akpanlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wisevivitisibudimij.pdfIn PDF document text
    • http://forti.in/userfiles/file/55975088769.pdfIn PDF document text
    • https://dlt-nkp.com/fileupload/file/83385656743.pdfIn PDF document text
    • http://audyt.rowerowaszkola.pl/imgturysta/files/bugetegejokigona.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/nixugepoforozop.pdfIn PDF document text
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/fugejowawekopulukikusawu.pdfIn PDF document text
    • https://aksusu.com/upload/files/56344458760.pdfIn PDF document text
    • http://ykzn8.com/upfiles/editor/files/15754731560.pdfIn PDF document text
    • http://texmet.pl/userimages/file/lesume.pdfIn PDF document text
    • http://wdnederland.nl/file/12985449195.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/61238276969.pdfIn PDF document text
    • http://tractortools.cz/ckfinder/userfiles/files/5006666530.pdfIn PDF document text
    • https://jjpremiers.com/files/48745218641.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/5773244927.pdfIn PDF document text
    • https://turasmobilya.com/img/editor/image/file/97882860369.pdfIn PDF document text
    • https://klcmekatronik.com/ckfinder/userfiles/files/fabiwizeluvovepeduvugogow.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/64493034405.pdfIn PDF document text
    • http://geoscan.it/userfiles/files/29022353461.pdfIn PDF document text
    • http://ourconn.com/userfiles/file/202109020053076315.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_off0000deed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEED 16744 bytes
SHA-256: 2635ac5f91dd8af2345204137495178043dc4fac00bc3b818041140d20d096f6
font_01_sfnt_off00010a9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A9C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000122b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122B3 10080 bytes
SHA-256: 4ab07b125a8e68a69925c03f80185442283f506d7888bc45a06308e42d956465