Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dc9256f6bb86de3…

MALICIOUS

PDF

69.2 KB Created: 2021-09-30 23:48:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 53a72bd15a165d8a2847e90d55dbb599 SHA-1: 9f33695f078ce623d4ff68792d0b1e72ff5509d2 SHA-256: 8dc9256f6bb86de39277b3fdac458a8920b5e244b13abec118972f7deeb46f31
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crewmak.ru/uplcv?utm_term=windows+phone+rom+for+android
    • http://foto-recepty.sk/images/fotky/26064291254.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614d3fd9d9487---40886036790.pdf
    • https://shopexpert.com/app/webroot/files/userfiles/files/jetorefuruxolel.pdf
    • https://nazragame.com/calisma2/files/uploads/xumogusabis.pdf
    • http://headrepublic.pl/images/files/54139398053.pdf
    • http://e-sportis.com/images/upload/retuvuduwo.pdf
    • https://economiadecomunion.net/ckfinder/userfiles/files/91503646037.pdf
    • http://relindalouisylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/51082776460.pdf
    • http://48bulls.com/js/upload/files/diziwofukane.pdf
    • http://pelejas.com/IMAGENS/CKFINDER/files/74821912329.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16147da5a674e4---xuzinon.pdf
    • https://maciejabramowicz.pl/upload/files/file/3330254460.pdf
    • https://www.edmcenter.xyz/ckfinder/userfiles/files/97468187789.pdf
    • https://voxel-avocats.fr/uploads/file/
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161410429c424e---muniremefi.pdf
    • https://www.algeos.com/js/ckfinder/userfiles/files/65609230176.pdf
    • http://goraku-sangyo.com/userfiles/file/70344971744.pdf
    • http://xageunion.com/userfiles/file/93471554521.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/ce4a3dbbfc5a0fd65b15bd1ac71a8674/72850203681.pdf
    • http://architettosirocco.it/userfiles/files/76138025017.pdf
    • http://coimbrasoftware.hu/images/uploads/files/19506419414.pdf
    • https://epagneuls-bretons.fr/caningest/images/file/45114101622.pdf
    • https://listapp.in/ci/userfiles/files/4897544563.pdf
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/161333d2ca8167---71284174923.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_off0000af2f.bin
a216aafb567ee6b74609bb002e533bdfe5e74800a96c75893e9c88dcc898a72f
pdf-font-stream PDF embedded font (sfnt) at offset 0xAF2F 15772 bytes
font_01_sfnt_off0000d6e7.bin
4426a9717c6365fea44a120712cffc40d86108a3106e607d7c4c5a392fd832a4
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6E7 10700 bytes
font_02_sfnt_off0000ef48.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF48 16792 bytes