Malicious PDF — malware analysis report

Static analysis result for SHA-256 86ab3dfb28fd8632…

MALICIOUS

PDF

82.1 KB Created: 2021-10-11 03:56:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f564a73c3917089ee6869dac50d1e4f3 SHA-1: 2089bcfd5aa02e63709f4e6cb1ce243afc1581c7 SHA-256: 86ab3dfb28fd86327e2de9e52b43efef2800a2df00b60f34ad6548803b7b3a53
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, presenting numerous URLs that lead to other PDF files, many hosted on compromised CMS upload storage or disposable hosting. The presence of 'utm_term' parameters suggests a phishing or SEO manipulation tactic to lure victims.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=introduction+to+basic+manufacturing+processes+and+workshop+technology+pdf
    • http://stmrcstvm.com/userfiles/file/2412130508.pdf
    • https://suacuachuyennghiep.com/uploads/files/14766600108.pdf
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/44156833855.pdf
    • https://appvid.eus/userfiles/files/wewese.pdf
    • http://ain.proximeo.com/ckfinder/userfiles/files/mofanegarufenugowawixalaf.pdf
    • http://visit-pune.com/userfiles/file/62314501258.pdf
    • http://zgkimsteszew.pl/img/upload/files/90248448105.pdf
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/6f08f121a9fd7ae6cc4bae2a125f9b68/defikuguwupuke.pdf
    • http://studioriggio.it/userfiles/files/vasufimaragakisuwif.pdf
    • http://husplaza.hu/editor_up/reminowoweviva.pdf
    • http://etenindex.nl/images/uploads/63514228023.pdf
    • http://skpizzasubs.com/uploads/files/61370394515.pdf
    • http://jenistudio.com/upload/FCK/file/68366096616.pdf
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/sunikemekovemizatoli.pdf
    • https://satuldelut.ro/ckfinder/userfiles/files/88251493817.pdf
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/c5f22a1efd904c248346458b27f32580/69409586193.pdf
    • http://nature-revive.org/files/file/josomifegiporor.pdf
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/sinume.pdf
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/0ca2d2c4316bfd5f778906a7610b9b23/89685955595.pdf
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/77719161993.pdf
    • http://vwtint.com/userData/board/file/29892364547.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/8sb5h8qe26279q3v7ar6rj5pe3/sezutuvumizokemifir.pdf
    • http://pumarecovery.com/userfiles/files/dimakamosuriromomuwude.pdf
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/ojb1g4evpu3n67ot5p6hc8duvn/53734194836.pdf
    • http://france-ex.com/images/blog/file/38859764546.pdf
    • https://mosconi.net/userfiles/file/24296363665.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_off0000d759.bin
14de1f4a3c355828bd4970935f3f5e186cf9b971c7bf855dbb1907542c492420
pdf-font-stream PDF embedded font (sfnt) at offset 0xD759 18420 bytes
font_01_sfnt_off000106a1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106A1 16792 bytes
font_02_sfnt_off00011eb8.bin
1afb00b22163200871ba4bdb7ba3d63f650f9f123285ffc4d9f566e107a99da1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EB8 11552 bytes