Malicious PDF — malware analysis report

Static analysis result for SHA-256 25d482dfeeb20450…

MALICIOUS

PDF

75.2 KB Created: 2021-09-12 16:16:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: df89e1b75bef0952ceaf8a59d1a42384 SHA-1: 8d5dacaa1c5a6096b53c9a74ac1b41e136e111e5 SHA-256: 25d482dfeeb20450f63cbc362dc546da5e8f116f75bdd1148e413352e925b70b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL structure and heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://olynskiconstruction.com/pics/file/gozufudafagosepokofudatu.pdf In PDF document text
    • https://cuacuonbentre.com/upload/files/90125100389.pdfIn PDF document text
    • https://karlschool.org/uploads/files/202109092138049781.pdfIn PDF document text
    • http://elitvorota.ru/f/file/26518980914.pdfIn PDF document text
    • http://myslizdrave.com/soubory/dasutatowipivube.pdfIn PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/nowawitakubonowukotimap.pdfIn PDF document text
    • http://materialdeestudo.top/userfiles/files/datalimekobafoj.pdfIn PDF document text
    • http://szguilong.com/userfiles/files/79699294183.pdfIn PDF document text
    • http://gesgo.de/userfiles/file/21472169404.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161364638a69be---88422623451.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161321605d7cef---63330004067.pdfIn PDF document text
    • http://evaemlak.com/userfiles/file///jijizagureniverurefefawu.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///2021090523944_634599290.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/68049300637.pdfIn PDF document text
    • https://locoffice.ru/userfiles/file/18193066720.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613012ff4a5f7---72909381595.pdfIn PDF document text
    • https://genia-groupe.fr/images/files/8249877181.pdfIn PDF document text
    • http://www.wiz-fac.com/uploadImg/file/65594423038.pdfIn PDF document text
    • http://arsvet.ru/img/upload/49711778674.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/53965475748.pdfIn PDF document text
    • http://ff-engineering.com/userfiles/files/59780504332.pdfIn PDF document text
    • http://hndgyl.com/v15/Upload/file/202196059122711.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=android+mobile+price+in+bdPDF 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_off0000c50c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC50C 10368 bytes
SHA-256: d032c1b1caf887133ed32e963ebf1afc73838105c1bc425db3c1d2766538c0a4
font_01_sfnt_off0000dc1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f42f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF42F 16724 bytes
SHA-256: a84d3c4aab48964cf0996f46013d61d4974803f5c57f1f747f9a988357551381