Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b21e1223c7ed60f…

MALICIOUS

PDF

80.1 KB Created: 2021-09-05 10:45:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 44cd314cb77980186803495f643440ee SHA-1: 321f93789bddf846da29bb8a5c7d5b847861dbc9 SHA-256: 4b21e1223c7ed60fa3213f9550d9b7b67b6d00ecaf19be758e9c47c9ed7f51b3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to potentially compromised websites and disposable hosting, suggesting a link farm or phishing lure. The presence of embedded URLs and the nature of the heuristics suggest it is designed to redirect users to malicious content, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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.ecostroyservis.ru/File/82580484164.pdf In PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/161105562c9845---10588892854.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/20218923888770.pdfIn PDF document text
    • http://xn--80aafbanafwvcftiqfecrg2a.xn--p1ai/pict/file/37297253226.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160ad97df3011e---soparefumamazudagarutenen.pdfIn PDF document text
    • http://uptownchantilly.com/uploads/files/doralusek.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/97a1d571d57d646b4d37efe4be3dcd71/28705477590.pdfIn PDF document text
    • http://beerskiboot.com/img/upload/file/namilurizadezed.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/e96cdc36b7a87695d7ce708c497e550b/65872308636.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160f5cf7543e8b---lukoges.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/2dcd2ddf38fede876ddcdac117abd995/bekut.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fd6ce0433b3---rikalogatuwabilutej.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b378cddc1c6---47780228325.pdfIn PDF document text
    • http://perrymanreunion.com/clients/f/f8/f8644f0eb9578147d5589f75b8c3e300/File/kelolilufafasar.pdfIn PDF document text
    • http://sclifeguards.com/clients/16854/File/pawarojibalezafizonat.pdfIn PDF document text
    • https://micsys.in/userfiles/file/deditu.pdfIn PDF document text
    • http://loaamtran.vn/files/usersfiles/files/66278560515.pdfIn PDF document text
    • https://norservis.com/files/files/31938649659.pdfIn PDF document text
    • http://architettoangeli.it/userfiles/files/winivoxasolilibexazudob.pdfIn PDF document text
    • http://jiuxingchaoshi.com/uploads/file/271526124084.pdfIn PDF document text
    • http://beergolfers.com/blog/images/file/6194931794.pdfIn PDF document text
    • http://minerva-collection.net/files/files/11456653897.pdfIn PDF document text
    • http://zhuoer.ltd/userfiles/file/zikibe.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee6871706c---97166196444.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=libro+para+abrir+el+tercer+ojo+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_off0000d579.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD579 17904 bytes
SHA-256: 28d9687d0afb2f70fb452935c1f4bc76a096b59772b301fe59993a8e8fa561a9
font_01_sfnt_off000102ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102EC 10568 bytes
SHA-256: a7e8a25122ac67f5bef47518a45e29e22f614518cfa8083463617aad3dafa3bf
font_02_sfnt_off00011ae1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AE1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1