Malicious PDF — malware analysis report

Static analysis result for SHA-256 dda5588fb61aedd4…

MALICIOUS

PDF

98.4 KB Created: 2021-09-23 14:28:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5e0e0e26337a91816a3c9ba5a48b66bd SHA-1: 392dc443fe9bf6181d4e45b3686c4c5e46689a55 SHA-256: dda5588fb61aedd4ea63bfd58c5b2e09504c4a5bdc5d1344d39deedd463b65c0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, redirecting users through multiple domains, some of which are hosted on compromised CMS platforms. The presence of numerous external URIs suggests an attempt to lead users to potentially malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9921

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://archism.ru/uplcv?utm_term=ielts+express+upper+intermediate+audio PDF link annotation
    • http://workcoop.org/fckeditor/userimages/file/20210922045828.pdfIn PDF document text
    • https://bbox.ru/images/shared/file/57102441478.pdfIn PDF document text
    • http://novo-foto.ru/ckfinder/userfiles/files/29087851279.pdfIn PDF document text
    • http://rajasthanmetals.com/userfiles/file/7663292410.pdfIn PDF document text
    • https://guclupin.com/calisma2/files/uploads/jugevivikodetu.pdfIn PDF document text
    • https://innotek.vn/uploads/news_file/fasubuwusevevowakas.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/11416305758.pdfIn PDF document text
    • https://ascii.tn/web/cgi/file/30556995415.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613ddfa5587d0---mexukudo.pdfIn PDF document text
    • http://pixel-pro.ru/upload/file/64644816984.pdfIn PDF document text
    • http://liavanhaeringen.nl/userfiles/files/51205491780.pdfIn PDF document text
    • https://valstybestarnyba.com/upckfinder/files/50686986685.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/c7hropbecmufj8ckv33oe4jad2/deredokixorevinurejuped.pdfIn PDF document text
    • http://www.aportecnica.com/imagenes/editor/file/nifalaxo.pdfIn PDF document text
    • http://rosesrealtyhomes.com/userfiles/files/87632589088.pdfIn PDF document text
    • http://barbusci.it/maisUserFile/file/63315143173.pdfIn PDF document text
    • https://rajaketiga.com/contents/files/33853171721.pdfIn PDF document text
    • http://dkind.net/userData/board/file/27681861035.pdfIn PDF document text
    • https://istanbularicilikfestivali.com/upload/ckfinder/files/vefitad.pdfIn PDF document text
    • http://saktigroup.in/uploads/91323768166.pdfIn PDF document text
    • http://sushi-belovo.ru/files/podarotamubodepoput.pdfIn PDF document text
    • http://haraj-alqunfudhah.com/userfiles/file/15311677103.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613cadb79e02f---87933778421.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f091.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF091 16892 bytes
SHA-256: e74c5b1d23d74b32682e28c1dcd335a63df0a86e04cf4c1334563ab8b95198ff
font_01_sfnt_off00010911.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10911 26356 bytes
SHA-256: 6867f15d6df795cff064e86db06ec17df304d84a1fafc0dddeb8803181cea428
font_02_sfnt_off00014a7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A7D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00016294.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16294 10704 bytes
SHA-256: a5d49908956002db009f987171cfee7ed486915e9f0c43787d423558a92fc7ad