Malicious PDF — malware analysis report

Static analysis result for SHA-256 d7d3b2f38962f88f…

MALICIOUS

PDF

69.3 KB Created: 2021-09-26 10:38:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e8dd2b15dd31d4d5366d7804719caac8 SHA-1: adaea9a802ca538ecd6a90aed83edc1ff64125d3 SHA-256: d7d3b2f38962f88fb0b6f8a998e9600b54881265500ffa0986676882e2130b4e
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 disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The presence of external URI heuristics and the 'PDF_SEO_DISPOSABLE_LINK_FARM' rule further support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://masan315.net/board/imagefile/file/27848308019.pdf In PDF document text
    • http://aeusjtu.pretty-match.com/upload/files/21637130376.pdfIn PDF document text
    • http://kronikarp.pl/ckfinder/userfiles/files/26107209422.pdfIn PDF document text
    • https://shinaltd.ru/images/file/kojapojekalimi.pdfIn PDF document text
    • http://bc-arman.kz/ckfinder/userfiles/files/xemujolopatevinatikerut.pdfIn PDF document text
    • https://accidentmatters.com/ckfinder/userfiles/files/75730602657.pdfIn PDF document text
    • https://egf.tw/test2/images/file/vevofujolubiver.pdfIn PDF document text
    • http://veterinariogiardinelli.it/userfiles/files/22755615481.pdfIn PDF document text
    • https://mehregancenter.ir/images/upload/files/80766163356.pdfIn PDF document text
    • http://ulrike-mayer.de/userfiles/files/39490319822.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/96338936312.pdfIn PDF document text
    • http://oreoltour.ru/sites/default/files/file/kakafujuxikawamew.pdfIn PDF document text
    • http://rhondachem.com/d/files/jaliratikuzu.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135da3376c61---pogazomuxanafinanadipo.pdfIn PDF document text
    • http://tottazo.com/userfiles/file/sefivebosum.pdfIn PDF document text
    • https://thaiahpa.com/flash/files/42454572799.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/pagoliwebefowipod.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc5baf02f4---17520891975.pdfIn PDF document text
    • http://seyrimerdin.com/userfiles/file/nulijilawa.pdfIn PDF document text
    • http://euro-ex.com/images/blog/file/82063690452.pdfIn PDF document text
    • http://digjamaica.com/app/webroot/files/98834094858.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/e28d4cfe80f24d1055af46bb98286aba/82954837107.pdfIn PDF document text
    • http://birkhoffhi.com/userfiles/files/94857070411.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=is+magnesium+a+metal+or+nonmetal+or+metalloidPDF 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_off0000ae6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE6C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c683.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC683 10644 bytes
SHA-256: c15643c93a57104a884e7aec4aaddefee9954ad1097cb3c094290d34b57cef8f
font_02_sfnt_off0000de95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE95 16056 bytes
SHA-256: 37e1d65b0e073d0274bc027011651631c1a11dc815853a1133fba0186ece283b