Malicious PDF — malware analysis report

Static analysis result for SHA-256 41e251557a908826…

MALICIOUS

PDF

86.7 KB Created: 2021-07-01 10:35:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 85c524d543721161a390fe0038ef9f2a SHA-1: 8e616727b8ce38bc4d23a31d25478dca1d40c3c0 SHA-256: 41e251557a90882615377761e78374339dd95b6253736f4c974c06f07542ba1a
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many embedded URLs pointing to compromised WordPress upload directories. These links likely serve as a lure to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847b77cd32e---72719110527.pdf In PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160796e7ba0f0b---73861673440.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608087da94879---87769687934.pdfIn PDF document text
    • http://abogadosaguilar.com/ckfinder/userfiles/files/94103974398.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084312d544c4---52082233735.pdfIn PDF document text
    • http://thankschicken.com/uploads/files/33284081923.pdfIn PDF document text
    • http://royalwedding.jp/images/blog//file/68874778086.pdfIn PDF document text
    • http://anvlaw.com/userfiles/file/82133208336.pdfIn PDF document text
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/4c6c2f7dfbcd04d83ba2c433e0ccb0ac/mezegewumunurini.pdfIn PDF document text
    • https://teyadegitimvideo.com/calisma2/files/uploads/48988484639.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/16089bca14c4cb---54483926158.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/utaqb53g796jvttvi3g0n86o3s/nazigudubakajukabutana.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/41010605842.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7ae58fbd0---29958501899.pdfIn PDF document text
    • https://beliangka.com/contents//files/39849657326.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/68518612809.pdfIn PDF document text
    • http://tgtech-auto.com/userfiles/file/bedikegu.pdfIn PDF document text
    • http://hjtech.org/admin/upfile/file/jufejor.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ac2adf9edc9---nofujafaminevoxe.pdfIn PDF document text
    • http://washchienluoc.com/upload/file/zabemovuzadanowaso.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/96072432449.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd3331b014---1245679720.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ac84ec6078c---muxitoful.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/91086631949.pdfIn PDF document text
    • http://bundoreh.com/fckeditor/files/file/zemitirupafewelitax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=jeanie+buss+and+lebron+jamesPDF 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_off0000eded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDED 17968 bytes
SHA-256: d74b0ab08bed4878e02562eabd3af94eeb7fb00588dc3f6c443204e9d65a0818
font_01_sfnt_off00011d26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D26 10672 bytes
SHA-256: 3459b4ed490f302571ab7fc11b3034755ad66b316042a7ea2ded3261a06e8fbc
font_02_sfnt_off0001357b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1357B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1