Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fb12dd1c127823a…

MALICIOUS

PDF

83.4 KB Created: 2021-06-30 01:51:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5571fef308a15f03b818a0d57e0e1d0a SHA-1: 4ec67fdaa2dbc057618afc0d789c2769c7bbfb05 SHA-256: 3fb12dd1c127823a6d796470a72514272c77adc84d82353c719ea64de4cfc764
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV and an ML classifier as malicious. It contains numerous URLs pointing to compromised WordPress sites, indicating it functions as a link farm. The presence of these links suggests the PDF is intended to redirect users to malicious content, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself is leveraged for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/f56d3938c34d1f51d25ee70e5079e026/tonipoxumupirikazu.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a5cbbeba24f---37345091693.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/0bb7166567019338dee6dc21eca8333c/suganoburesidaluzuga.pdf
    • http://komputerzagrosze.pl/userfiles/file/sipiguxevobetetisoje.pdf
    • http://cjatkinson.com/userimages/65245760806.pdf
    • http://starwindows.ie/ckfinder/userfiles/files/fadonutoz.pdf
    • http://www.hydro-tg.pro/upload/file/50830485315.pdf
    • http://xn--2-140-swe8h.xn--p1ai/files/pozewoloxovowofixefusileb.pdf
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/dfp7p37sghb6m68r0fhe935ov3/tafomogug.pdf
    • https://hpsoft.shop/upload/files/doxov.pdf
    • http://spreewaldatelier.de/img/editor/file/68119298622.pdf
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/160741ffbc0558---74695823770.pdf
    • https://musikkursus.dk/userfiles/file/loweluje.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/lfltl021vnvl4l8tra55n5mhmj/78879899879.pdf
    • https://aslimitada.com/userfiles/file/82460447882.pdf
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/f32da508ea6700e1159dee1186ba98bf/dulixed.pdf
    • http://imssp.by/data/images/fxeditor/file/towupubakejoka.pdf
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9c4d5c321---40041677541.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608015aecfe4f---zasapukuxofatoralivinali.pdf
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/00d31f334969d20a2be721bd458e3b50/fawip.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608116090f76c---babitemamufoduweb.pdf
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/fe54459a8d715657e59bb902aec0989c/welulofule.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=round+square+face
    • 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_off0000e363.bin
ce8b61319cd44ea4f3ad49437dabbdc843c30b7306e6d8eb8eaeff4fdbe813af
pdf-font-stream PDF embedded font (sfnt) at offset 0xE363 10524 bytes
font_01_sfnt_off0000fb51.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB51 16792 bytes
font_02_sfnt_off00011363.bin
06d48cb980cbc3ffaba54cc952facbbba177d162b40660858b2b15412ea7a42b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11363 17032 bytes