Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1231c7c9816fa6f…

MALICIOUS

PDF

76.7 KB Created: 2021-09-23 17:52:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5de3191e4e23b6464f6b83a8d0f96bba SHA-1: 84926e16c2b31479726339c2cc780e4942e381fb SHA-256: d1231c7c9816fa6f810232c4ae7a7e12fba614bd01ae06157f2f40ce20a2984d
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to PDF files hosted on compromised CMS uploads. This suggests the document is likely part of a phishing or spam campaign, potentially used to distribute malware or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://mami-m.com/Uploads/userfiles/files/91929222183.pdf In PDF document text
    • https://orsam.org.tr/paketler/ckfinder/dosyalar/files/mapifan.pdfIn PDF document text
    • https://www.mds-horizons.com/upload/files/5609208806.pdfIn PDF document text
    • http://playoz.com/ckfinder/userfiles/files/61639826604.pdfIn PDF document text
    • https://cecprint.com/images/file/detixojobe.pdfIn PDF document text
    • https://netiko.fr/img/Data/file/88711091992.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/p41qds10ep6ivagg2aoiqigdm2/wamesitaxozozu.pdfIn PDF document text
    • http://gangwonbnb.com/FileData/ckfinder/files/20210901_078C6BA6274FD2A9.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/320176487.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec28d4bbc9---segaz.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-9-11/20210911215434250408.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161345d9b4d5b1---80718896710.pdfIn PDF document text
    • http://barahi.com/assets/userfiles/files/raligedajak.pdfIn PDF document text
    • http://kiddeefire.com/media/userfiles/files/nozapatuzepitisipuren.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/60946007446.pdfIn PDF document text
    • https://at1apigroup3.com/contents/files/57694364369.pdfIn PDF document text
    • http://cofetariafraguta.ro/UserFiles/file/12317468048.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7e9d124c5---wugawuw.pdfIn PDF document text
    • http://studiolorenzino.eu/userfiles/files/65784673700.pdfIn PDF document text
    • http://inhome360.ru/admin/ckfinder/userfiles/files/dulisebesapuwagorovomuw.pdfIn PDF document text
    • https://koltoztetes-szallitas-lomtalanitas.com/ckfinder/userfiles/files/18838817912.pdfIn PDF document text
    • http://radissonhoteltraining.com/userfiles/file/vovobatokafofunariwapur.pdfIn PDF document text
    • http://www.dereformasenalicante.com/archivos/files/kimiwinowaxidipurezazuwib.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=best+haircut+for+slim+facePDF 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_off0000c9bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9BB 10652 bytes
SHA-256: d3ad2bc375defdf9bae8491e3462a56058ada90f410efb4fef70c663b689ab7a
font_01_sfnt_off0000e22b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE22B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fa3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA3D 16536 bytes
SHA-256: 3827f3b160d2da56d28b95042e1e5562ab3b9b83bf1d63a995bcae047ca90a32