Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4903c7a05d39f2a…

MALICIOUS

PDF

84.8 KB Created: 2021-09-10 00:18:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a94aea0e8f1c4e86f348bc1e2e22dcb7 SHA-1: d3ef18def9d7cad90dda02557cebf3b445356f26 SHA-256: c4903c7a05d39f2a88bbd7591acad09c104aa8832efd2869ad5547905ef3ebe1
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a ClamAV signature and an ML classifier. It contains numerous embedded URLs that point to compromised WordPress sites and other domains, functioning as a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a non-clustered link farm on disposable hosting, suggesting an attempt to redirect users to potentially harmful content.

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://www.educationsexuelle-ecole.ch/ck/ckfinder/userfiles/files/kuzazabogikuxam.pdf In PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/161377bc9b6758---kamodof.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/50372152017.pdfIn PDF document text
    • https://semut73.com/contents/files/71589018471.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/nodurifunezoro.pdfIn PDF document text
    • https://corpeverest.com/ckfinder/userfiles/files/60870747870.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134d88393470---64328872379.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161320ca437bcb---nubusonob.pdfIn PDF document text
    • http://misterholidaysanprisco.it/userfiles/files/16875226384.pdfIn PDF document text
    • https://jajugroup.com/ckfinder/userfiles/files/situxen.pdfIn PDF document text
    • http://tbeaindia.com/userfiles/file/60126779096.pdfIn PDF document text
    • http://mrpokedb.com/uploads/files/98493949993.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/bixisozisorazugilura.pdfIn PDF document text
    • https://istocdukkan.com/userfiles/files/kamiwuzalul.pdfIn PDF document text
    • https://tierlistei.ch/downloads/32637061485.pdfIn PDF document text
    • http://z500.si/files/piwemuferetelozogij.pdfIn PDF document text
    • https://zenithservicos.com/userfiles/files/92842586364.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/2667029253.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16131bac241029---6004444574.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/lezes.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210907_3A39D2217FF74366.pdfIn PDF document text
    • http://retailpark.bg/uploads/wysiwyg/files/mizomafolebevezi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+download+android+emulator+in+pcPDF 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_off0000e6ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6FF 10684 bytes
SHA-256: 13ee2ce2179aeac662aa96d799a89278c8a7fc94ee87a744db33f037e19b0047
font_01_sfnt_off0000ff6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF6B 17780 bytes
SHA-256: adf69c5d617851f36368158c2734d754493332a1d08ab2c5e56ec0a7f8fa1a37
font_02_sfnt_off00012d63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D63 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1