Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0cf8f2fff28a9b2…

MALICIOUS

PDF

84.6 KB Created: 2021-09-10 03:03:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c7bfeb959c01baad1eb56241da907a67 SHA-1: b0793b646ea81b8dd6de5d0dd775d7c37e640cde SHA-256: b0cf8f2fff28a9b27c56089ecb7f03ac9bb470e5026c1f0f685a24fc563335c3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with several heuristics indicating it functions as a link farm. Notably, some links point to compromised WordPress upload directories, suggesting a tactic to host malicious content or redirect users to phishing sites. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://pavillonwohlen.ch/userfiles/files/19724525848.pdf In PDF document text
    • https://leganordavigliana.it/uploads/file/resipagubozebifaxuvawu.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/14653714904.pdfIn PDF document text
    • http://ansing.nl/userfiles/file/vorinepadedi.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/wafero.pdfIn PDF document text
    • http://eternoohydro.com/d/files/25235629473.pdfIn PDF document text
    • http://fitviewer.com/files/file/38789728376.pdfIn PDF document text
    • http://iqlacpro.vn/emotive/upload/files/15192564851.pdfIn PDF document text
    • http://ever0036.com/assets/uploads/ckedit/files/20210902191043.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16134eeb094a79---28846043832.pdfIn PDF document text
    • http://brickform.cz/obrazky/files/44518238865.pdfIn PDF document text
    • https://rieker-consulting.eu/files/file/21701995735.pdfIn PDF document text
    • http://rivebistro.net/ckfinder/userfiles/files/dedanalobetefeler.pdfIn PDF document text
    • https://calson.garment-pro.com/ckfinder/userfiles/files/53321152064.pdfIn PDF document text
    • http://freestyler.cz/img/file/nivolirore.pdfIn PDF document text
    • http://bekescsaba.varosom.hu/userfiles/files/titotubimibemova.pdfIn PDF document text
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/96698212783.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613665580138e---79271276368.pdfIn PDF document text
    • http://pnc21.com/files/fckeditor/file/6110367936130697da49ab.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/15020d6e4bf057c6af6d54380bfd3e63/22233797137.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613616a9717c8---rukorikupemigoluvepedixu.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/s2baogq88ugns50ienagoafg5j/balemadaxu.pdfIn PDF document text
    • https://www.sesc-am.com.br/Selecao/ckfinder/files/42524323523.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=view+blocked+numbers+on+androidPDF 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_off0000e3ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3CE 18728 bytes
SHA-256: 6f2b4252ae0f190b011800c2ccff645c2b54f9e9ecf6b901b7c2f4c1e6ea631f
font_01_sfnt_off0001138d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1138D 10820 bytes
SHA-256: f371dde3117dae8b2d5a90f12b865f190f937fba2ff922e0b15f486d4848a77f
font_02_sfnt_off00012c8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1