Malicious PDF — malware analysis report

Static analysis result for SHA-256 a64bccbaa5ad4302…

MALICIOUS

PDF

79.2 KB Created: 2021-09-18 12:25:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3f5102f1300a236d3fa2b03b51d6f56c SHA-1: 7944689fa6b89adce269c05ce597f4b402389dc9 SHA-256: a64bccbaa5ad4302efc82fb81783ab7a2c2e027738ca51b5deabd34fe2df0c52
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://cructi.ru/uplcv?utm_term=keep+service+running+when+app+is+killed PDF link annotation
    • https://eurosan.pl/user_images/file/xuretatelavavudetevag.pdfIn PDF document text
    • https://landtop.com/filespath/files/20210901222547.pdfIn PDF document text
    • https://smartmedia.ro/app/webroot/files/userfiles/files/18538433435.pdfIn PDF document text
    • http://vinhthuan.vn/upload/files/62397816149.pdfIn PDF document text
    • http://kunjipsc.com/uploads/files/77115869818.pdfIn PDF document text
    • https://pasifikendustriyel.com/userfiles/file/45849984706.pdfIn PDF document text
    • http://balletpanov.com/uploads/files/dutobevexuzu.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/as30alco1740pns7tmbstpmf54/vizoviranit.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16144ca05a7763---vawuzogufodawidewerazo.pdfIn PDF document text
    • http://shop-exclusive.cz/userfiles/file/vazukuselotalejulenev.pdfIn PDF document text
    • http://brukikostka.pl/uploads/page/file/dadawekabilegosa.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/beletisaputat.pdfIn PDF document text
    • http://yingtailong.com/upload/file/210910065849715070fgoxgodbly9k.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/2988193016.pdfIn PDF document text
    • http://sbkf.org/files/files/tasorew.pdfIn PDF document text
    • http://metalzilemboeventi.com/userfiles/files/muriwudutoz.pdfIn PDF document text
    • http://salonorganica.ru/upload/files/tubupagor.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/c2c63412eda545203b8dc9d359a3cbb5/zepaw.pdfIn PDF document text
    • http://www.kyousei-fukushi.or.jp/system/ckfinder/userfiles/files/85989915650.pdfIn PDF document text
    • http://sysquare.com/UserFiles/files/sosibewevepepuzero.pdfIn PDF document text
    • http://twfindia.in/userfiles/files/runidugiwebodexume.pdfIn PDF document text
    • http://spain-ex.com/images/blog/file/67985290719.pdfIn PDF document text
    • http://tw-echen.com/uploads/files/202109131749521159.pdfIn PDF document text
    • https://onsale.social-push.cc/data/fckeditor/files/64587119502.pdfIn PDF document text
    • 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_off0000cfaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFAF 10908 bytes
SHA-256: 3a313a35cc990e70344dd03226ca2fb93b43d0f6924fd45d20e89d9f704a7472
font_01_sfnt_off0000e8b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B7 17540 bytes
SHA-256: 8234ad81d5a95d12ee5fe2a3522af847faf64df64c8a40bef2ad06f812df841a
font_02_sfnt_off0001168b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1168B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1