Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf1c2aeb6e95a197…

MALICIOUS

PDF

78.2 KB Created: 2021-09-12 19:56:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 5b699787ecd869d972a61b86ff7437f7 SHA-1: af4896e91c9c9ff4040ed8f6bb76e1ac3052ff99 SHA-256: cf1c2aeb6e95a1974f057ed33bcf190abbc309a5aef1114ddafb05cabda3fe96
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The document body is unreadable, but the heuristic firings and URL analysis point to a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://apatity.verlauf-ekb.ru/admin/ckfinder/userfiles/files/riwuga.pdf In PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/jitekazoxaxunave.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/likizukutabuterowisit.pdfIn PDF document text
    • https://i-try.tw/upfile/files/2021/09/03/kotagokosokomezagodakupuf.pdfIn PDF document text
    • http://kanalizace-ul.cz/userfiles/file/36340782261.pdfIn PDF document text
    • http://vucert.vn/uploads/files/24761444242.pdfIn PDF document text
    • http://dichvu12h.net/userfiles/file/25460948585.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/55e19d6c8f3004a15df179abedc775be/lokifewanunamepe.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613032f02c895---jetonujumegomelu.pdfIn PDF document text
    • http://studiodugnani.it/userfiles/files/68308088513.pdfIn PDF document text
    • http://qualityspices.in/ckuploads/files/birosibasakutase.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c4b006557---jipasezeru.pdfIn PDF document text
    • http://autoset66.ru/admin/ckfinder/userfiles/files/64929144459.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/65186442370.pdfIn PDF document text
    • http://aloisiquadri.it/userfiles/files/51417624904.pdfIn PDF document text
    • http://cnsgafgl.netsociality.com/upload/files/21801613725.pdfIn PDF document text
    • http://bjjiffy.com/upload/4277365540.pdfIn PDF document text
    • http://retrievers.su/ckfinder/userfiles/files/85086916934.pdfIn PDF document text
    • https://sklepbonus.pl/userfiles/file/18710632429.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/jigikenotafelutidesaru.pdfIn PDF document text
    • http://descanso.verareyes.com/ckfinder/userfiles/files/4774554812.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=android+app+development+companies+in+hyderabadPDF 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_off0000ce11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE11 16700 bytes
SHA-256: 66aad0fd1daa329656c1b8eb77340d3a6c4cdeb0727fa0a4a90a6b56503c0e25
font_01_sfnt_off0000f92e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF92E 11080 bytes
SHA-256: 7f9e54e50011ba8255c57aa7021d8fc1479295f59910e640cb908c9b3122518d
font_02_sfnt_off0001129d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1129D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1