Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5c51df567067f13…

MALICIOUS

PDF

91.8 KB Created: 2021-09-11 04:33:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 38de93829759a1a36bedf3acbbdde010 SHA-1: e5b419145bbb98a6c13695a707025f519ef026e1 SHA-256: b5c51df567067f1322ec0bb0b4885f5e665fa4c947d2fa317c345c2341374762
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites and other disposable hosting. These URLs are likely intended to lure users into downloading further malicious content or visiting phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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 http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16136d6954aefe---57807482974.pdf In PDF document text
    • http://gioiacompany.net/images/upload/file/91989799952.pdfIn PDF document text
    • https://jagominum.com/contents/files/69977794834.pdfIn PDF document text
    • https://panificioilcavaliere.it/userfiles/files/roderefagedatu.pdfIn PDF document text
    • https://sangolongphuong.vn/longphuong/news/files/33376328259.pdfIn PDF document text
    • http://gdwtechnology.com/fckeditor/file/guvobunazijifek.pdfIn PDF document text
    • https://stillwaiting.org/userfiles/file/tevupaxugadabogefi.pdfIn PDF document text
    • http://china-miyaco.com/img/file/20219611256.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/72qi2co4b1v3q3pqgevgibc74h/jerufekesulemesalan.pdfIn PDF document text
    • http://aokisuper.com/ckfinder/userfiles/files/vafigaxazalolakinezojidi.pdfIn PDF document text
    • http://shrlie.com/upload_fck/file/2021-9-7/20210907005528170697.pdfIn PDF document text
    • https://melz-feu.ru/upload/82787794567.pdfIn PDF document text
    • http://www.dkmodels.net/ckfinder/userfiles/files/21143322234.pdfIn PDF document text
    • https://movimientofamiliadejesus.com/images/uploaded/file/72956141816.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16132cc6a9813c---78269269030.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/doxezavuzogagulirulebele.pdfIn PDF document text
    • https://we-plus.tw/ckfinder/userfiles/files/46898825575.pdfIn PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/fazawovigozimorivefobeme.pdfIn PDF document text
    • https://hotelpancharatna.com/assets/userfiles/files/67103302848.pdfIn PDF document text
    • http://podhoru.cz/userfiles/file/zilukebibafasisitejuvul.pdfIn PDF document text
    • https://bhopalliteraturefestival.com/mpsdp/uploads/files/woxupezojozatexeni.pdfIn PDF document text
    • https://www.notusweb.com.br/ckeditor/ckfinder/userfiles/files/pukiwutiminolit.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/33272555635.pdfIn PDF document text
    • https://shunnasato.com/69621370137.pdfIn PDF document text
    • http://soojuspilt.ee/files/file/refazoxare.pdfIn PDF document text
    • http://cyclad.org/UserFiles/file/gugosatexibedimijowem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=android+transfer+data+from+one+phone+to+anotherPDF 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_off00010095.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10095 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000118ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118AC 10700 bytes
SHA-256: 51bcc13d8b401508c956f030ec866b620a13fd77820269f8d25c3fc3ef06c9e6
font_02_sfnt_off000130ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130FF 18156 bytes
SHA-256: b536d653d9c8f43feea3a37d66392055fa26d247adc95499f4e1ded152800f9b