Malicious PDF — malware analysis report

Static analysis result for SHA-256 b631509402c20805…

MALICIOUS

PDF

73.1 KB Created: 2021-09-07 21:32:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 57ca344ed066bd31a8d56744ba254946 SHA-1: 0a50f5486851554645e20b69feb304fc9dab9ae3 SHA-256: b631509402c2080511bb930bacbb5227452fed0f593bfecdc3311904baffd4f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution attempt. It functions as a link farm, directing users to multiple compromised WordPress sites hosting PDF files. The presence of external URIs and link farms suggests an attempt to redirect users to malicious content, likely for credential harvesting or further malware deployment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609af63e72c55---98554664117.pdf In PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609a6b063e770---rawenatesafuxagasudujo.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d39bf32d4e---xupozixugibuxabozivakiler.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/79vgm8mfilkm69ovtegvpkal47/13365962635.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609b30dc04309---lixabasepifavivu.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/384925046578219003d808943c398e5a/71989298778.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/visekodetadul.pdfIn PDF document text
    • http://karlsbach.de/userfiles/files/tazometanefinuz.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/jthmra770nkmcl2j44jpcu97f0/rawarawem.pdfIn PDF document text
    • https://swift-tw.com/lcc/upload/files/nopenagokidozefenoju.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160767d381dc91---45451982919.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/butagejezanatibuzab.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///dinulonukujasori.pdfIn PDF document text
    • https://miaousland.fr/ckfinder/userfiles/files/xigolum.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/160889e2bbc956---13405900736.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/8a265ea7970c03c746173c6f9508c03d/48757726448.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a90fc4667de---40154490356.pdfIn PDF document text
    • http://cupta.org/userfiles/files/20210822031041.pdfIn PDF document text
    • http://ahdjcm.com/upload/files/militisewixiw.pdfIn PDF document text
    • http://kezmosas.hu/files/file/mulinomanafemagupide.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160e1cbb59b7e5---60951128567.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16095ae0c0056e---witorofosi.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/nd7vnd0kp4ev7k6qe02oa9isve/misaka.pdfIn PDF document text
    • http://carrozzeriabosini.net/userfiles/files/85789324641.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f209976ca7---mejiditefixolisefatiwejor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=prepositional+phrase+worksheet+for+grade+8PDF 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_off0000bd80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d592.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD592 15340 bytes
SHA-256: c5fcb6fb2d523c77eb4233440de1074112f69f6021d61b31d0c730eae1046b1d
font_02_sfnt_off0000fc8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC8A 11164 bytes
SHA-256: fc4b09c4ec860d36ebca82f357add238a123c231d979998fea63980e22b6e853