Malicious PDF — malware analysis report

Static analysis result for SHA-256 c213bf83b813994f…

MALICIOUS

PDF

68.4 KB Created: 2021-09-25 01:08:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: eacf075ad50aa0017c56064e2d5d2ac1 SHA-1: 0bdd0c29b80a14cfe0f485cab67c353c692b2cd7 SHA-256: c213bf83b813994f75bbf998d0b2656fabe1bf973b6aa5cbefc55f8bcc499424
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 a link farm, with many embedded URLs pointing to potentially compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document designed to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://successalpha.team/upload/files/25221349700.pdf In PDF document text
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/kumiboforened.pdfIn PDF document text
    • http://laureysnv.be/uploads/files/60320025060.pdfIn PDF document text
    • http://archi-m.ru/userfiles/file/bilitorapenu.pdfIn PDF document text
    • http://gpe-el.pro/ckfinder/userfiles/files/75878378140.pdfIn PDF document text
    • https://ms01bet.net/contents/files/nibosironopado.pdfIn PDF document text
    • https://amigo-shop.105h.net/upload/files/nukeperexarota.pdfIn PDF document text
    • http://3dtechgroup.com/uploads/image/files/7364767655.pdfIn PDF document text
    • http://drzwiukryte.pl/userfiles/file/24023938424.pdfIn PDF document text
    • http://aardbeienfeesten.nl/uploadimages/files/vepoxuzeredirojakinu.pdfIn PDF document text
    • https://giltmorestukko.hu/ckfinder/userfiles/files/66689389191.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c6e455c648---99424123284.pdfIn PDF document text
    • https://eltdb.com/UserFiles/files/wiposamoxodiku.pdfIn PDF document text
    • https://vinadesigndanang.vn/uploads/image/files/dukevoj.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/8ep9kn9c2au53nm5lbjn2g39f2/10266348241.pdfIn PDF document text
    • http://24x7taazasamachar.com/assets/ckfinder/core/connector/php/uploads/files/96003403226.pdfIn PDF document text
    • http://hrampetraipavlavosstanovlenie.ru/content/images/user/file/35629154013.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/161386fd20ccc8---toralokolisi.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/zuxitolukuxig.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/2asdi25ps5e1838n97ra5h85cm/wimipuxidiforiza.pdfIn PDF document text
    • https://digireg.gr/upload/tovesepimu.pdfIn PDF document text
    • http://cdjuchuan.com/upload/files/88493373064.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/83489546382.pdfIn PDF document text
    • http://thomas-zigon.de/images/file/33542812726.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=classic+emulator+for+nes+apkPDF 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_off0000afa2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFA2 14352 bytes
SHA-256: bcd7a49296b374ea1b7cbb1859c5265eb4512210e0595bf9f1eceabea2bd4c85
font_01_sfnt_off0000d332.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD332 10864 bytes
SHA-256: 7c6ae3ba68c368580f4c3a1efd3f71d3d29912dba6599a3d23ce326663d0fd12
font_02_sfnt_off0000ec51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1