Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8d76fd38471090d…

MALICIOUS

PDF

72.2 KB Created: 2021-09-14 11:53:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8b48d439e3564219cd84580834dbd075 SHA-1: eeeb0d15a54694d8d0828b04f5e60e104d67bed8 SHA-256: f8d76fd38471090d0e51151552019614d3b6feae90448e0f57e75c50a7f08f9d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and link farm heuristics supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://synerhu.ru/uplcv?utm_term=kako+gledati+tv+na+androidu PDF link annotation
    • http://vitrine-prof.com/files/66422290183.pdfIn PDF document text
    • http://www.southpointinstitutehowrah.com/admin/uploads/file/26238462165.pdfIn PDF document text
    • http://severstroysnab.ru/userfiles/file/sebitekexinewav.pdfIn PDF document text
    • http://hbaoge.com/upload/files/lesino.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/11639852916.pdfIn PDF document text
    • https://laptopserwis.com/app/webroot/media/files/69153412840.pdfIn PDF document text
    • http://yanartextil.com/firma/files/31476108765.pdfIn PDF document text
    • http://altiro.nl/home/tjerk/file/1559315573.pdfIn PDF document text
    • http://sxnqx.org/upload/file/Fl202109070655549015.pdfIn PDF document text
    • http://atrsara.ir/resource/files/84012721208.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/161316aea6a3dc---98122750414.pdfIn PDF document text
    • https://ajur.rest/uploads/userfiles/file/xawiwenibekolema.pdfIn PDF document text
    • http://ottuk-e.org/userData/board/file/87352862367.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2c9a5c4da833993e0449598261f19ef1/runibujomo.pdfIn PDF document text
    • https://novsport.com/content/File/mabaforeladusuruzem.pdfIn PDF document text
    • http://falconltd.pl/cache/file/kagubeza.pdfIn PDF document text
    • http://imhkayseri.com/resimler/files/nixidukasekojawed.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/c7a8998f8bf924542a68d7a9fbb87e68/46096505430.pdfIn PDF document text
    • http://sake-tori.com/images/library/File/bulukubesuxowululop.pdfIn PDF document text
    • http://conganbacgiang.vn/app/webroot/uploads/files/15732840142.pdfIn PDF document text
    • https://grupa-energia.pl/attachments/file/govosikezedanuxinuda.pdfIn PDF document text
    • http://kythuatviet.vn/uploads/userfiles/file/jinijokarurugawu.pdfIn PDF document text
    • http://xecuoihuyhoang.com/uploads/userfiles/file/63892910945.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_off0000b6a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6A9 10504 bytes
SHA-256: 097b0f59ad1edda9de92dc635c2d82381f9f10539cf6c2de9ecf754074d94194
font_01_sfnt_off0000ce7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE7F 17372 bytes
SHA-256: e810c90792073ac183f53b08cd70074e46c3f27f355cdac6ea78bbae1d4f1c5d
font_02_sfnt_off0000fb47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB47 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1