Malicious PDF — malware analysis report

Static analysis result for SHA-256 139482348a27c134…

MALICIOUS

PDF

89.3 KB Created: 2021-09-01 08:55:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d051f1775e804438447520ec62d998d5 SHA-1: 8f9978bb9422967b8c861d31a3d5f7e7da6e3f3b SHA-256: 139482348a27c13423c6c1d54ff470216304516b02b0d1fd4e20aadc6e56108b
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the link structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://valeaflorilor.ro/img/uploads/file/56894601365.pdf In PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1612c71cbe1738---22606224660.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/tobulufawubopi.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160959c348b095---miduzamuv.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/160955004ce719---31164243950.pdfIn PDF document text
    • https://justbuymeds.net/userfiles/file/fukipawes.pdfIn PDF document text
    • http://vitalenzyme.com/uploads/fckupload/file/wurirebuwedosil.pdfIn PDF document text
    • http://castudio.eu/userfiles/files/gitebotavaj.pdfIn PDF document text
    • http://muaah.ca/userfiles/files/85942574425.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/96625116754.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/39022927286.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/jjig36uoogqvk7buc0fa1jlvg6/sadutupasedekeviduwu.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ff58f9bfc90---79674404042.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609e083ba63e7---duxesutodipuzoxu.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/zobesoxafakagafagum.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3d1b0d839---gifeninumifufupazunekani.pdfIn PDF document text
    • http://greenearthgardens.org/userfiles/faguginutajujigumixosim.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c187dbcc02---fulawaxatu.pdfIn PDF document text
    • http://liebherr-tr.com/userfiles/file/51172387576.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/133d7e4e3a66bcfb5d2652511f2e265b/89463578637.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/b5754905231ecfa6c22a05115dc63482/26782415388.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/mhnejj55hnvf7sn86rtgsocej3/bufobividofekagojaj.pdfIn PDF document text
    • https://thegioidongphuc.net/ckfinder/userfiles/files/tuwuwikexokun.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/fubevuwozofusasisikagef.pdfIn PDF document text
    • https://tutorlookup.com/ckeditor/ckfinder/userfiles/files/mizagasaluwigu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=astrophotography+with+gcamPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB59 18072 bytes
SHA-256: cb83d1bd98f225daf7e76896d8c70939d68b49d4a86a32b44e8d2ab7b1baf3e9
font_01_sfnt_off00010a43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A43 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012254.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12254 17896 bytes
SHA-256: 178a5c4f086b125f325d1e8237c26d14cab34bb4bd0220d65151e120779aa40f
font_03_sfnt_off00013d95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D95 10720 bytes
SHA-256: ef3a4864a6531901019061579407d424afb9a5b2433b7d7616843775381db9e6