Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bd338e85a7a0366…

MALICIOUS

PDF

75.5 KB Created: 2021-09-02 15:58:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 7f1e5098aa3bd804d98d053ff6530c94 SHA-1: 4d86526b4dd08fc7185b4199e663a4adb23cfc15 SHA-256: 6bd338e85a7a036626ccc01c55cc28567b76f86d5900df2ed92e0c18e45fc62a
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting a phishing or malware distribution lure. The embedded URLs, while some are marked benign, are part of a larger pattern of directing users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1b0a6ee7a---61973339230.pdf In PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c864541c826---xiwapuziwarapezowokoxi.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dcde050198d---daxeniremarobelexikise.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/96eedc1bc595e104e4fa5503cef1a316/narilolixor.pdfIn PDF document text
    • https://hbphoto.ca/resimler/files/54516956591.pdfIn PDF document text
    • https://kaptenhoki.com/contents/files/59043583279.pdfIn PDF document text
    • https://terlickodds.cz/www/www/fckphotos/file/34211448693.pdfIn PDF document text
    • http://taixingchem.com/uploadfile/file/20210826105117172.pdfIn PDF document text
    • http://greenld.com/userfiles/70830439339.pdfIn PDF document text
    • http://radis-rrl.ru/userfiles/image/losixaxagowurote.pdfIn PDF document text
    • http://aromaonly1.com/yamituki-n/uploads/files/rijasawu.pdfIn PDF document text
    • http://halaljones.com/uploads/files/30899818019.pdfIn PDF document text
    • https://basundharamart.com/userfiles/file/75844901695.pdfIn PDF document text
    • http://kirakuramenandsushi.com/uploads/files/rozokogane.pdfIn PDF document text
    • http://isystem.hu/ckfinder/userfiles/files/saniwopak.pdfIn PDF document text
    • https://bearings.vn/images/ckeditor/files/81583013284.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/3915366392.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/d260595598c01cf9f1ee81f1584300da/81831966423.pdfIn PDF document text
    • https://mujeresenmovimientoplus.com/userfiles/file/nidugudifonudixusufa.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/43400403171.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608d3ce04c368---12390934329.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/23793926154.pdfIn PDF document text
    • https://gachbinhduong.com/upload/file/44160926136.pdfIn PDF document text
    • http://www.tsahimmongol.com/uploads/images/files/juwem.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a5b4086d87a---97571294552.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=best+pdf+to+word+converter+app+freePDF 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_off0000c34d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC34D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB64 10680 bytes
SHA-256: bd97f31c17ae71ff18f89326b4ed51a55cf96929d1292de5e4036a260019c751
font_02_sfnt_off0000f425.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF425 16764 bytes
SHA-256: 5e01fee9cda6ea22e5d3475eaeeb85cc8a19d731322ff0c78dd8afcf78de5694