Malicious PDF — malware analysis report

Static analysis result for SHA-256 28f4557cb52b56e2…

MALICIOUS

PDF

85.9 KB Created: 2021-07-02 04:53:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ac18be23a7cc86cad3444caf55eb9fd4 SHA-1: 8b8a42778204887e458555e39d9ea9ab0c8ced97 SHA-256: 28f4557cb52b56e2c63298b79d88856e3e8fd59b801abbcc4dda535db0fcf9eb
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as containing a link farm hosted on compromised WordPress upload storage, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV also strongly indicated maliciousness. No scripts were extracted, but the presence of numerous links to potentially malicious domains suggests the document's primary purpose is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c896e0159dd---17040281916.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca784ccafc---58905322500.pdf
    • http://hawks79.com/clients/85064/File/43485009837.pdf
    • https://budapestpainter.hu/ckfinder/userfiles/files/finuwobosezitak.pdf
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160870b6bbcb31---xarokuvipirojenofexefoga.pdf
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609c31526cfde---28759987515.pdf
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160ad5ab112525---pafemugix.pdf
    • http://pro-group.ru/userfiles/files/35664169016.pdf
    • http://rollfactorytogo.com/uploads/files/nepebuzugitujexuboto.pdf
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d069bdcc2ef---gavowelafexaj.pdf
    • https://bishopsalamatkhokhar.org/userfiles/file/madefagividubidipo.pdf
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/7dc4303dab94356ff0cafea8820228b8/viten.pdf
    • http://crmrealty360degree.in/userfiles/file/28120597786.pdf
    • https://sunrise-photon.com/upfiles/editor/files/77389778613.pdf
    • http://smclassof57.org/clients/34860/File/jixakewagikoromev.pdf
    • https://hissekurban.com/resimler/files/kuvuvizuza.pdf
    • http://czdashan.cn/uploadfile/file/2021051005274073499.pdf
    • http://lpkgoodframeupvc.com/userfiles/files/33804524464.pdf
    • http://remaining-mc.de/userfiles/file/fidifurudajasorimuz.pdf
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099226bed746---33923541635.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/jjs3kcmm3i7bnqocvcpeesct24/53622976306.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a31be7a51d6---62550775295.pdf
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/37836087877f5f9940a8c12458e37607/1979852813.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=bibliography+in+report
    • 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_off0000ea46.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA46 16792 bytes
font_01_sfnt_off0001025d.bin
9228b62ac02c3eb46fbc0e0a7c2e97a79c9480f2da2fae9c025506a6db3195c2
pdf-font-stream PDF embedded font (sfnt) at offset 0x1025D 10672 bytes
font_02_sfnt_off00011a88.bin
124f4a05a6baa687801a3da1eb6f9f4106e1d39bed021dbe2a9a6fcf713cc0d2
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A88 18292 bytes