Malicious PDF — malware analysis report

Static analysis result for SHA-256 a27e3140d10d300a…

MALICIOUS

PDF

81.0 KB Created: 2021-09-06 03:50:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: b90b3524209390c44684ebbb2d5daff5 SHA-1: a10f56ec635fb20750b949e3b17e49aea9cb0f3d SHA-256: a27e3140d10d300afbbf5ac27ae282e7431b70470076c68824d8b306861a308d
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress sites, suggesting a phishing or SEO poisoning attack. While no scripts were extracted, the structure and URL patterns are indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16090e9fe9d6bd---29212832525.pdf In PDF document text
    • http://cc-loges.com/uploads/file/vasoralakekofulaxodenuke.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/vanebukupemojado.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d428e95d26---74578568065.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/vikexofarunelu.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/9544a12a3d951ec77096d59389ea7a89/32327446361.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fe9be163d57---14558461724.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/t3edk9it0hqceafp8a7na07l56/komazenabezajozorozawos.pdfIn PDF document text
    • http://zoltysnieg.pl/pliki_wyswig/files/52772615484.pdfIn PDF document text
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/1d18275f7ed7d1326b64bcf42335cd60/16302165772.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/72250009601.pdfIn PDF document text
    • https://www.roadsafetyrental.com.au/application/third_party/ckfinder/userfiles/files/57136319842.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/37937648584.pdfIn PDF document text
    • https://xaydungdonggia.com/app/webroot/files/images/pages/files/45227953445.pdfIn PDF document text
    • http://dongtienlamnghiep.com/upload/file/63686740322.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084a07ab2548---41559901567.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/16300316391.pdfIn PDF document text
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/f5ecdd00b9a9c2fa885dae6081a30b3b/nibisaremizidunedob.pdfIn PDF document text
    • http://the-bom.kr/upfile/files/73879062757.pdfIn PDF document text
    • http://beastyenergy.com/userfiles/file/gukatutamogazilo.pdfIn PDF document text
    • http://villa-carlshorst.de/sites/default/files/file/9142090650.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160771f2ccdc76---jabasutesitet.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160783b253a05e---sozunonogo.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/l6t4qfge4kecfebajaot6jsbj5/bepugumezaxokumed.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/faguxumugutiwuropajor.pdfIn PDF document text
    • http://zwickerfoto.hu/_user/file/xiruxepogekisaxipixituv.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/d419278b8bba5933411574e2475850b5/nadijavamege.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=geography+of+ancient+egypt+worksheetPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d810.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD810 11044 bytes
SHA-256: a6ef141aff542cdc0f4e92e27d2467f9558f6dc565a230209f9a62b60c59c7d2
font_01_sfnt_off0000f1dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1DC 17100 bytes
SHA-256: fefae2430160f742400d0127755afed233e6720cf1653a05339249691428ca6e
font_02_sfnt_off00011dc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DC7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1