Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8e07ad01fdc631d…

MALICIOUS

PDF

76.0 KB Created: 2021-09-04 03:27:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 22471715d6fa14e915335eefabb8df1c SHA-1: 274df04890e3038729cf78499f6298b5189cbc74 SHA-256: a8e07ad01fdc631da5ddb8605ece59c22959757b2d51b8f1db2174d13b01fbff
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites and other disposable hosting, which in turn host other PDFs. This behavior is indicative of a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for distributing further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 http://kedehg.com/ckfinder/userfiles/files/biposafonijisi.pdf In PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/ed95cf9372bfa786702dca4c836bd12a/90923099442.pdfIn PDF document text
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160751ca9dfabf---welafipumeza.pdfIn PDF document text
    • https://perfecthospital.org/FCKeditor/file/44967563371.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/16095b7fe8f63f---wufezurega.pdfIn PDF document text
    • http://constantcontinuity.com/membership/data//files/13948511123.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c42994f3312---7841864824.pdfIn PDF document text
    • http://haenuri.net/ckupload/files/gafosaxazavegarafajiralej.pdfIn PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/98355508089.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160e1699d922fe---mojabaxevovaluxaburol.pdfIn PDF document text
    • http://warraichmeats.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079358b06cde---32762656815.pdfIn PDF document text
    • http://m2mus.pro/clients/b/b1/b1ca46fdb12d68e762e4a8b3318caec0/File/76574622869.pdfIn PDF document text
    • http://computerdoki.hu/user/file/vijomik.pdfIn PDF document text
    • https://letstravelforacause.com/miet/assets/files/96576789071.pdfIn PDF document text
    • https://gazeta-msp.pl/user_files/File/67608267129.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16071a89dd3f0c---tasizazoga.pdfIn PDF document text
    • https://petrovsky14.ru/docs/files/kesetadigi.pdfIn PDF document text
    • http://dietgame.net/admin/fckeditor/data/file/20210821222035.pdfIn PDF document text
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/eacbf948bf4aba9e1b9ca445ab4dbf27/75697320432.pdfIn PDF document text
    • https://talaa-obour.com/webmisr/uploadwebmisr/file/misabijas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=design+of+masonry+structures+by+dayaratnam+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_off0000c74d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC74D 15960 bytes
SHA-256: a01343b41f4dedd9b4f2dbb364a4d45270c88769cd1c0d6b4a24539dd52b59ba
font_01_sfnt_off0000f022.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF022 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010839.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10839 11272 bytes
SHA-256: 89040e924f2beac3594a5e5568f995795b7655668bbdbd02672f334af58a3fc0