Malicious PDF — malware analysis report

Static analysis result for SHA-256 34b838a491a975b3…

MALICIOUS

PDF

77.2 KB Created: 2021-06-10 21:18:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 8c9974a7ef9ef27de63dd5e9e9575188 SHA-1: 91e4b2152aa9a7265a355fcf5b4a63aabb9f7b29 SHA-256: 34b838a491a975b346cfbb0d441d41a555d61c88ad0f00b0ad4a7e70a831df84
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded links pointing to various domains, many of which appear to be compromised WordPress sites hosting PDF files. The heuristic firings indicate a link farm strategy, likely intended to direct users to malicious content or phishing sites. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://queure.ru/uplcv?utm_term=teleserye+tv+replay PDF link annotation
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1606f309b093e9---fomavosolunirifubobasareb.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/f3abc6fd0aad514aacb581f9c373f4a5/tefet.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609479bd3f906---walupagoganepepifelu.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/160943608995af---gokakuwujotexifu.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/5mdqd23qi6i8ablt88h9erg9v7/pinikosir.pdfIn PDF document text
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/i3cbe6o2uvpb9g3o0qst3citge8oaso2/jitinabaxobiredijusuz.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/nugedewa.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/zokarej.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d513550a4---kuxidivepexil.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16080670501e8e---18337290709.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/98caf6d9c10fade0dd1cd80355b07362/kezinitun.pdfIn PDF document text
    • http://amphorabeautyclub.com/campannas/file/22805342362.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160864b426668c---tumututobagipoja.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/86rlhkth5279kov5j62821eop7/mobopaj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000db99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB99 4924 bytes
SHA-256: 555714852056863c00a9b6120d7df94006f574b325b7daa98b8d98dcc5a478a0
font_01_sfnt_off0000ec72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC72 10708 bytes
SHA-256: f1674914fa1f203e697d8ac5963436c896f42db4674519ed8d053d4e99eaa164
font_02_sfnt_off00011145.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11145 16204 bytes
SHA-256: 541fa2b6826b0add99b7d5a173ef1e6a5567607b5192f75b810eb17d6a563501