Malicious PDF — malware analysis report

Static analysis result for SHA-256 d57a45527aaa36d2…

MALICIOUS

PDF

75.3 KB Created: 2021-09-07 08:19:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a0950a4e1881c3b1c4b476fb402813f7 SHA-1: 29f4195aee02278fb908db7b05d74ea4be9e7fde SHA-256: d57a45527aaa36d2220712b0331a2a38df0a5ec56d04dd696d30f96c7e7d83c1
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting. These links likely lead to phishing pages or malware downloads, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9907

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://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/db7d083d6868bdd24fe75f87771ffa7c/37537835541.pdf In PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076856cafcd1---35798062833.pdfIn PDF document text
    • http://www.dogwoodagility.nl/ckfinder/userfiles/files/libobatilatipapifuwi.pdfIn PDF document text
    • http://ort168.com/upload//ckeditor/files/xavavosazekor.pdfIn PDF document text
    • http://hk-sai.com/ckfinder/userfiles/files/vajitasaminitew.pdfIn PDF document text
    • http://andrelandberg.com/userfiles/file/pupasukedogevuju.pdfIn PDF document text
    • http://htwy.com/upload/file/peguso.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/16107e9ff14d53---wobajaj.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/06b43cdffaac5aa411db00ebe5a98e13/82379181670.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/towubatitukasanila.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7219bda57---4053184763.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/c83hb65eqngn3eorvc3vl1hi73/18719948.pdfIn PDF document text
    • https://tootooair.com/FileData/ckfinder/files/20210903_0B3D30A10AB30B4C.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/783efedcfe9c46efb047774d3696b27a/tisinuzesozikaf.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/dij3i6ht4kqn90ukd4m2icjura/xijozizulegipalowu.pdfIn PDF document text
    • http://eg-connect.com/uploads/editorfiles/file///lezofuxaninewewodeweleset.pdfIn PDF document text
    • https://rowadalbyt.com/userfiles/files/kerikexerasez.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/79969128168.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611ad25656157---wakusepiralitavupen.pdfIn PDF document text
    • https://communeouchamps.fr/userfiles/file/dirojusobugotina.pdfIn PDF document text
    • http://etenindex.nl/images/uploads/jerov.pdfIn PDF document text
    • http://pogologistics.com/ckfinder/userfiles/files/rijuzozaregakoruvo.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/temunefawobajajizemirad.pdfIn PDF document text
    • https://shastriratanchatterjee.com/ckfinder/userfiles/files/nekowesefatavuxidik.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/86973938270.pdfIn PDF document text
    • http://pokemom2.com/uploads/files/vuzizo.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a713ba267ac---90976855335.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=patterning+and+algebra+grade+7+worksheets+pdfPDF 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_off0000c3f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3F9 11144 bytes
SHA-256: 158fd3cce730744b441d64f0b51e7c3dc089751f96f6c77bbaa78a7b9095e247
font_01_sfnt_off0000dda4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B6 16068 bytes
SHA-256: 1986393d65808e45365b902b0baac4951cd99af29fb48d8027dc70875305252e