Malicious PDF — malware analysis report

Static analysis result for SHA-256 37f5f7c9f3d72752…

MALICIOUS

PDF

81.9 KB Created: 2021-09-07 17:44:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c047e55ec1acefe741db31ee639334b4 SHA-1: d53538f283716699fccae53995bbb4f9d12b9a03 SHA-256: 37f5f7c9f3d727523311796f4774b5e221127e020acb6d5724cc62772b01f0fb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, suggesting a phishing or malware distribution campaign. While no scripts were explicitly extracted, the PDF structure and link farm indicate an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cb1c8f4f9e3---24739827573.pdf In PDF document text
    • http://besteva.com/upload/files/xoxewebajikufozeru.pdfIn PDF document text
    • http://casinodanmarkjackpot.dk/userfiles/file/powabunezeke.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/c71br5hg9h0ko7749740solu36/28368521118.pdfIn PDF document text
    • http://appletechsolutions.com/userfiles/file/tetojexavokefa.pdfIn PDF document text
    • http://autoachtercamper.nl/userfiles/file/jepokifizikuxixabewimavo.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/4ec745405273433788df60962eb2576f/49624776707.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/mvtj4n3tkjjgqm8d1s9oh5lv6p/56025524929.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/23680352171.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/940dc961dc598a31a98f9f71800e1d07/donomutarilidesonijo.pdfIn PDF document text
    • http://podushka.by/files/files/gafukodubetozaludoxis.pdfIn PDF document text
    • http://visit-pune.com/userfiles/file/17996311500.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16097d0e987721---98449293917.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/23286888734.pdfIn PDF document text
    • http://jan-fotografie.nl/upload/files/pamedazegisarosabasab.pdfIn PDF document text
    • http://www.supair-lux.hu/ckfinder/userfiles/files/befugusevuba.pdfIn PDF document text
    • http://shinhwajudan.com/userData/board/file/gopofuku.pdfIn PDF document text
    • https://rrr71.ru/upload_picture/78749446930.pdfIn PDF document text
    • http://vxclouds.com/userfiles/file/daperelanelopowobevu.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/deeab97a99c460967dba49e2539293f1/82380966293.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2cd7374a5b4fbdd8ee5fbbf6e6e44700/31814847221.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4b9dd5e84---fosokureseborikofe.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a2c95f85b43---xotimigosoxijelewefikavo.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16110510d86e33---40831111038.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609633c176650---4585712956.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=forms+of+visual+communication+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_off0000dc5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5B 17116 bytes
SHA-256: 78b4069d083975fcf546a68197079c8b6b632d48b677f258960619856f108df3
font_01_sfnt_off0001090e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1090E 10792 bytes
SHA-256: 706b9f2fb682ca5328f9425f934e69bd39e227586517011002ca59d745d15085
font_02_sfnt_off000121ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1