Malicious PDF — malware analysis report

Static analysis result for SHA-256 106826dcb3d43409…

MALICIOUS

PDF

82.0 KB Created: 2021-09-05 19:34:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 98937bec6f11ae24af58856c6597f9ed SHA-1: 94b21529c160605dd07c9cd406364ac4366c4fbc SHA-256: 106826dcb3d434096c50d3369edc0bc2a5bf627f9ceb613f7e287f7d00fddbb6
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The embedded links and the nature of the heuristics point towards a spearphishing attachment as the initial access vector, with the potential for exploitation upon clicking the links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://philabc.ru/uplcv?utm_term=superpowers+list+pdf
    • http://miroslaws.com/ckfinder/userfiles/files/xusujujewimepotapu.pdf
    • http://enotecagaribaldi.it/userfiles/files/futuvatusenuzutasopakito.pdf
    • http://aggengr.com/uploads/CMS/file/56294411905.pdf
    • https://www.tahitotfaluovodak.hu/ckfinder/userfiles/files/nojazakipatirof.pdf
    • http://fujiya-burbank.com/uploads/files/lotefeka.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ac134ae0fbb---jowekatumise.pdf
    • http://circuitoinsulargc.com/documentos/file/30016481680.pdf
    • http://cathyknightwaite.com/ckfinder/userfiles/files/mulitutamisetukitamo.pdf
    • http://yanartekstil.com/firma/files/24076850812.pdf
    • http://deborahkay.com/ckfinder/userfiles/files/sakoduvebulila.pdf
    • https://rubenoferro.com/userfiles/file/38016231836.pdf
    • http://hotel-gerard-dalsace.com/upload/document/xowovarog.pdf
    • https://perfecthospitals.com/ckfinder/userfiles/files/dasukapoba.pdf
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/gujezu.pdf
    • https://noithathoaphat11.com/upload/files/gitemaruxetalike.pdf
    • https://globalybm.com/ckfinder/userfiles/files/1625871573.pdf
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1612bc067e8523---78287391289.pdf
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a03bc4c6d4f---26517911532.pdf
    • http://yesilderecine.com/admin/editor_resim/file/43810105646.pdf
    • http://badaranquehablar.com/userfiles/files/jasaverugomika.pdf
    • https://singhaniabrothersltd.com/ckeditor/ckfinder/userfiles/files/55265783007.pdf
    • http://fred-robin.com/ckfinder/userfiles/files/tojiwedaritafef.pdf
    • http://kstarsmall.net/userfiles/file///jifarejitix.pdf
    • http://precedent.by/_newsite/images_from_html_editor/file/87495595960.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160786313aa3a2---10588031305.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd49.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD49 16792 bytes
font_01_sfnt_off0000f560.bin
9c3c3c44dc96f51d3f2d3dab9213d37c65692525d58e180f602182362356be80
pdf-font-stream PDF embedded font (sfnt) at offset 0xF560 10484 bytes
font_02_sfnt_off00010d55.bin
1fae163c98c3911e5d4b31e42a27e8fead05ecf0514b6b1314e7e5ccb2d96e74
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D55 17908 bytes