Malicious PDF — malware analysis report

Static analysis result for SHA-256 e6713e478fb2eb9b…

MALICIOUS

PDF

100.3 KB Created: 2021-09-03 04:15:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2eb52a899de2b88753e58b216f4cd067 SHA-1: bbea45ef32a71fb3db270972b64f9efb5e45880b SHA-256: e6713e478fb2eb9b9a4768324822c442de6c3a393df92df0d6827d324126706f
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to compromised CMS upload directories and disposable hosting. These links likely lead to phishing pages or further malware delivery, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 https://carsen.sk/editor_uploads/system/files/82221163525.pdf In PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff20762739---budexorufepojonebu.pdfIn PDF document text
    • http://kuhomania.ru/ckfinder/userfiles/files/gobuluzokenew.pdfIn PDF document text
    • https://augsburger-dartliga.de/uploads/file/vamomejedotonarosetaba.pdfIn PDF document text
    • https://etonbio.com/newsLetters/images/file/15002863292.pdfIn PDF document text
    • http://sbnjl.com/userfiles/files/musofogubimuba.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160896ae800a92---16292163565.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/uks0jnb4s2sql718enjpjppqar/93650736569.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/13654077501.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dda2cd6011e---jupaxakaxixixibazeg.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/ofi4odogcdjo58hvlt6etuh1jh/nozesu.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160e6940ee0db5---xufufovizolurutivububi.pdfIn PDF document text
    • http://solarwindependence.com/ckfinder/userfiles/files/31110830707.pdfIn PDF document text
    • http://tipsclubcr.com/campannas/file/77493564242.pdfIn PDF document text
    • http://cpils.com/userfiles/file/80231741799.pdfIn PDF document text
    • http://biaikatolikus.hu/files/file/nebivowaxizufuxibaro.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612c11cd4d9a7---26714079865.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160738d5c82033---54957076071.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=audco+valves+catalogue+pdfPDF 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_off00012575.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12575 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013d87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D87 18116 bytes
SHA-256: 05714ba966917ae27856942ce8df2be4355eba36da3cf9680c0db689ea1e6d70
font_02_sfnt_off00016be1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16BE1 10648 bytes
SHA-256: de545bdd9a049cfb9c96dabc430e374a918fb82f5f04dce9a6e4faab1b5d4362