Malicious PDF — malware analysis report

Static analysis result for SHA-256 2be70df1f5e96420…

MALICIOUS

PDF

71.4 KB Created: 2021-09-17 13:52:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 26d0ff91dc4d7d4e98a00ad7630feaf9 SHA-1: 3feaf921c4235616a9e35f1b3809d331c87e410c SHA-256: 2be70df1f5e96420718daaf60f7189abadf57f1f87218cd8e9158a3b32285342
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with several URLs pointing to compromised WordPress sites and disposable hosting, likely to distribute further malware. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 http://wmc21.com/ckupload/files/wasiwavolazede.pdf In PDF document text
    • http://climtech.com/files/files/9586039470.pdfIn PDF document text
    • http://eca.or.th/ckfinder/userfiles/files/61669826996.pdfIn PDF document text
    • http://ateliergermain.org/sites/default/files/file/70217131300.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/12n3llvtk2ckg8riugpq6qa18t/75176856911.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/34d5db7127bcebfb5b1963e3954eed74/22804068288.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/bd32ff7a84079d8c0f21ae9d65be8db1/korena.pdfIn PDF document text
    • http://maroba-zirndorf.de/file/maregudasu.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143ccfb45bc4---rutebu.pdfIn PDF document text
    • https://vico-immobilien.com/ckfinder/userfiles/files/romepisod.pdfIn PDF document text
    • http://keyflounge.nl/userfiles/file/seduzupagajo.pdfIn PDF document text
    • http://lsphc.com/userfiles/file///nezaguvokovibefonevaxa.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/nevogixib.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/tifunugubakovanadopozok.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/berazabeximujokupojami.pdfIn PDF document text
    • http://sd-admin.fazendapenaazul.com/ckeditor/uploads/files/ronuf.pdfIn PDF document text
    • http://coaching-scolaire.net/userfiles/file/20425650663.pdfIn PDF document text
    • http://webinaris.biz/ckfinder/userfiles/publics/files/45559636301.pdfIn PDF document text
    • http://encino.ilovepokebar.com/uploads/files/warogen.pdfIn PDF document text
    • https://fotofidelity.cz/userfiles/file/3743567687.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb5e207ef7---60400957718.pdfIn PDF document text
    • http://hoangnamjsc.com/upload/files/30803390248.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=essentials+of+geology+13th+edition+pdfPDF 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_off0000b564.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB564 16408 bytes
SHA-256: b8ed1f391dece5548d6c6601a7f256f545b54e5fe6f260e31a7ee797588b6e2c
font_01_sfnt_off0000decc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDECC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f6e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E3 10996 bytes
SHA-256: 09d71fca485e0f2e6a32b1ef83fac350de3a4d4a78670a5a628e0b533637f823