Malicious PDF — malware analysis report

Static analysis result for SHA-256 3afc19cd08686048…

MALICIOUS

PDF

81.6 KB Created: 2021-09-17 09:19:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 636de01d97e3d7ed4ab963db22400251 SHA-1: bdc3dd52b44a7944128c52162a54d0ae785f513c SHA-256: 3afc19cd08686048b226fff11282302222e2fcf7416d14aadef4dc3f5f27b673
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a significant number of external URLs. Several heuristics indicate this PDF is part of a link farm, with some links pointing to compromised CMS upload directories. The embedded JavaScript and the nature of the URLs suggest an attempt to redirect users to malicious sites, likely for phishing or to download further malware. ClamAV also detected this as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://infrive.ru/uplcv?utm_term=queen+dugu+watch+online PDF link annotation
    • https://et-auditing.com/userfiles/files/43297208082.pdfIn PDF document text
    • http://sushinamu.com/uploads/files/govivof.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/18796771969.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16141feebda3b2---menusuwuludi.pdfIn PDF document text
    • https://happycolaborativo.com/uploads/files/57518522388.pdfIn PDF document text
    • http://esistore.be/userfiles/file/94733011839.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/161347a33a61af---zosufudam.pdfIn PDF document text
    • https://wotfiles.com/ckfinder/userfiles/files/romuvabodusixetotiteri.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/wixitumozuri.pdfIn PDF document text
    • https://readandenjoy.ae/userfiles/files/sewexinodado.pdfIn PDF document text
    • https://samsungklimamodelleri.com/upload/ckfinder/files/leratufitaputow.pdfIn PDF document text
    • http://the100voicesofgospel.ch/fichiers/newsletter/file/49489819197.pdfIn PDF document text
    • http://iviltra.lt/images/files/zomefafagibipanewur.pdfIn PDF document text
    • http://synfarm.com/upload/files/vurej.pdfIn PDF document text
    • http://jamalcar.com/userfiles/file/sobibopipubos.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/lojutadosiko.pdfIn PDF document text
    • http://pijntherapie.be/uploads/files/bulafenuxurewonu.pdfIn PDF document text
    • http://rabwork.com/media/file/62535066794.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16130be663594b---68010946985.pdfIn PDF document text
    • http://theponghop.com/upload/files/lefasiselezivazegutuw.pdfIn PDF document text
    • http://carneiro-sa.pnh.pt/js/ckfinder/userfiles/files/50392989345.pdfIn PDF document text
    • http://jadeite.ru/images/file/negofofitinanisedipazonum.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_off0000da62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA62 17872 bytes
SHA-256: af71bd3115d902ddb7c8ad887fab63e8f3a7c6aed7e40f49e1ea9d49f30be1a2
font_01_sfnt_off0001087b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1087B 10628 bytes
SHA-256: 6612664da52097b3dfcce989925634074d1b8b78a3ddcc8a1342679cf20b62af
font_02_sfnt_off000120a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1