Malicious PDF — malware analysis report

Static analysis result for SHA-256 63addec0d21d8231…

MALICIOUS

PDF

82.9 KB Created: 2021-09-18 18:11:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: dcd3d98593526cfcce5c75d281e656b1 SHA-1: f6d4688b579ad09500a330963616c7b97e188695 SHA-256: 63addec0d21d8231e31e843141bc67859e3930cff56b98e6f04df2b425c64e10
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that function as a link farm, directing users to potentially malicious websites. Several heuristics indicate that these links point to compromised CMS uploads or disposable hosting, suggesting an attempt to lure users to phishing or malware download sites. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://inwebjor.ru/uplcv?utm_term=human+is+prokaryotic+or+eukaryotic PDF link annotation
    • http://erh-hu.com/userfiles/file/jesabibo.pdfIn PDF document text
    • http://moscowfashion.net/content/xuploadimages/file/79943069753.pdfIn PDF document text
    • http://asr-net.ru/uploads/files/faniliw.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/4ed93a1912ba2857ddbdd2c5e69f0569/juwafenukimimi.pdfIn PDF document text
    • https://perfectprojects.ro/userfiles/file/82447549155.pdfIn PDF document text
    • http://audyt.rowerowaszkola.pl/imgturysta/files/32049089640.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135c8504056c---20688470116.pdfIn PDF document text
    • http://hzkontejnery.cz/ckfinder/userfiles/files/9969846399.pdfIn PDF document text
    • https://francois-daulte.com/ckfinder/userfiles/files/kititegu.pdfIn PDF document text
    • http://associatedreclaimed.reclaimedoils.com/userfiles/files/januzezujiwufi.pdfIn PDF document text
    • https://forumhrdbekasi.com/webroot/userfiles/files/bezirunegujapamuwezatire.pdfIn PDF document text
    • https://darshanam.com/ckfinder/userfiles/files/birupuzoxagedazizofigux.pdfIn PDF document text
    • https://olgunbey.com/upload/ckfinder/files/47344708887.pdfIn PDF document text
    • http://shopabrang.com/images/files/munafu.pdfIn PDF document text
    • https://mklaassen.nl/images/file/walivadiwabuwinozufofiso.pdfIn PDF document text
    • http://style4.allwebeasy.com/userfiles/files/85411703392.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161424c85d02bc---24214331354.pdfIn PDF document text
    • http://attep.com/home/sandbox/domains/heekee.com.hk/public_html/ckfinder/userfiles/files/90358973538.pdfIn PDF document text
    • http://twinmd.ru/userfiles/file/zekalaguliz.pdfIn PDF document text
    • http://sydjpg.com/images/upload/file/20210910_130743_199.pdfIn 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://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_off0000d91a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD91A 10784 bytes
SHA-256: 5b5a6b203f593a00be70b748bba81daf86000fc20378692a0af5f7501690917b
font_01_sfnt_off0000f1f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F3 20296 bytes
SHA-256: 6da815ec2e6118c9d68af41a9f381f254770c773f6722d7f53b7e07041caef0e
font_02_sfnt_off000125e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1