Malicious PDF — malware analysis report

Static analysis result for SHA-256 42ae12e55be415d0…

MALICIOUS

PDF

73.5 KB Created: 2021-09-19 11:52:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a0667bf40c67130685b8b47b30755211 SHA-1: f7554c89a7f593b7b44d2ca599662d8563677495 SHA-256: 42ae12e55be415d0d42ec881310dba01aebd04d4b4e88ce421a7a5012132de62
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised WordPress upload directories and other disposable hosting. These links likely serve to distribute further malicious content, such as other PDF files, to potential victims.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://photo-ostrov.com/ckfinder/userfiles/files/kirarekawufetixojupaker.pdf In PDF document text
    • http://kbautotech.com/board/datafiles/imagefile/vebaziwolamexatukozewo.pdfIn PDF document text
    • https://trystsalonri.com/images/file/68386158956.pdfIn PDF document text
    • http://pijntherapie.be/uploads/files/10738629245.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/niserexepexisimudidobumu.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133623371e3b---8900306156.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/87754622190.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/59362345376.pdfIn PDF document text
    • http://sb-78.ru/files/file/ruzemowamevitetaj.pdfIn PDF document text
    • http://yongqingtech.com/d/files/dibepitekul.pdfIn PDF document text
    • http://shanghaiqingchen.com/upload/files/pipaxekubimat.pdfIn PDF document text
    • http://tsradviseurs.nl/mailing/images/photo/file/84527357360.pdfIn PDF document text
    • http://crimesla.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xogebilopevunepesapidumov.pdfIn PDF document text
    • https://hotararicedo.ro/files/files/78083201406.pdfIn PDF document text
    • http://xn----7sbjvweekof5d.xn--p1ai/files/files/98432993787.pdfIn PDF document text
    • http://8njl.com/userfiles/files/zeguluzira.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/16138507204388---botexexokomuwut.pdfIn PDF document text
    • https://anitacalderon.com/ckfinder/userfiles/files/fusazigazebem.pdfIn PDF document text
    • http://tpokebar.com/uploads/files/nisopazijegiximuvinabugu.pdfIn PDF document text
    • http://gaytonfa.com/upload/files/61502099616.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/f9dc609fc77f3583c8fc846c79d68fe6/tebulipakowijinuxoli.pdfIn PDF document text
    • http://irvine.songhakbbq.com/uploads/files/juwibomagilefifozibuzebip.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/420bfe74349d5927163075ce4a7cea14/63720652796.pdfIn PDF document text
    • http://ccforum.kr/uploads/file/1631420451.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16140e5ed6398f---79206472686.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=wow+io+scorePDF 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_off0000bed1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBED1 9892 bytes
SHA-256: 126e0dfd7a4fe0c9921b6d867eff35291e23b8f013f585faa0980455e77c299a
font_01_sfnt_off0000d4d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ece2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE2 16836 bytes
SHA-256: fffc84a920dc1ae772bb992c90bb8828a9d423f579285602c1f60a8f6eacbc89