Malicious PDF — malware analysis report

Static analysis result for SHA-256 981589a82cdbdc78…

MALICIOUS

PDF

71.8 KB Created: 2021-09-27 13:01:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 2826ca9c04823f015d179e2f6cb0fbbb SHA-1: 203f06ac9027b36fe9f87c64772830bc157d0824 SHA-256: 981589a82cdbdc78b653a451a730044a3ce0fb6ddd10c0440c68647916c57893
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://www.stock2morrow.com/ckfinder/userfiles/files/59877537038.pdf In PDF document text
    • http://administratieindex.nl/images/uploads/paxesulusolebo.pdfIn PDF document text
    • http://xn--80aatg4aaaddkhfhbf3evf.xn--p1ai/ckfinder/userfiles/files/59506946045.pdfIn PDF document text
    • http://studiorumeo.it/userfiles/files/tetono.pdfIn PDF document text
    • http://chiangmaicharmingtravel.com/ckfinder/userfiles/files/38777458368.pdfIn PDF document text
    • https://deshpanday.com/ckfinder/userfiles/files/29824209788.pdfIn PDF document text
    • http://hostingureitings.lv/uploads/userfiles/files/rutixarajukilavosufaj.pdfIn PDF document text
    • http://dlabiura.kbo.pl/ckfinder/userfiles/files/kasavunipuwufoli.pdfIn PDF document text
    • https://exclusivelimoservice.com/ckfinder/userfiles/files/74660404411.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614cb35fad27d---tuxowekajerudupav.pdfIn PDF document text
    • http://elard-group.com/ckfinder/userfiles/files/fejasimujipawevojawavaz.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ebf0318cc---820500927.pdfIn PDF document text
    • http://palletgoanloi.com/img-dn/files/zakelogukenasafidumi.pdfIn PDF document text
    • https://superpackeg.com/userfiles/file/nedosixuxasipurabumalo.pdfIn PDF document text
    • https://autoskola-scp.com/files/84562724642.pdfIn PDF document text
    • http://abwingstop.com/uploads/files/27766504495.pdfIn PDF document text
    • https://serpavenger.com/ckfinder/userfiles/files/82108971777.pdfIn PDF document text
    • http://xn--nellieskche-0hb.de/userfiles/file/65302104808.pdfIn PDF document text
    • https://casalindasbakery.com/ckfinder/userfiles/files/lelikosekurujenexofafur.pdfIn PDF document text
    • https://techinnsrl.com/writable/public/userfiles/file/lafumojipis.pdfIn PDF document text
    • http://capitaldanceacademy.com/userfiles/files/lekidokate.pdfIn PDF document text
    • https://giltmorestukko.hu/ckfinder/userfiles/files/32850781591.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/b9e717b3321d4befaf9241664713c84d/vopabaj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=diskdigger+pro+file+recovery+downloadPDF 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_off0000b339.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB339 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB4B 17520 bytes
SHA-256: bf6f40cfd367e88c229f96d53d8538eec62336bd06921441b43388428e617650
font_02_sfnt_off0000f84d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF84D 11056 bytes
SHA-256: cf1c43b3569342d25069c2e318598379df7773980778d34add4f1bc9343c362b