Malicious PDF — malware analysis report

Static analysis result for SHA-256 83fbf7e82f835538…

MALICIOUS

PDF

71.2 KB Created: 2021-09-17 02:48:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 601ac780c4266fb3345e760661bec9d8 SHA-1: 394a6a85b5cfdb672a25a9d6b819c970f998b725 SHA-256: 83fbf7e82f835538f8ecba699f0e799e23f6ad25d5391725784832810ff3e7d8
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://nomylo.ru/uplcv?utm_term=justice+league+watch+online+2021 PDF link annotation
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/161363361b3fba---26545022387.pdfIn PDF document text
    • https://satnamunicipalcorporation.com/admin/ckfinder/userfiles/files/tibupujedatagepuxep.pdfIn PDF document text
    • https://www.tamilsaga.com/ckfinder/userfiles/files/lasufeta.pdfIn PDF document text
    • http://manavpublicschool.org/manav/userfiles/file/87931325303.pdfIn PDF document text
    • http://beautifulmoda.com/userfiles/files/ximinomusew.pdfIn PDF document text
    • http://konakelektrik.com/userfiles/file/24296338432.pdfIn PDF document text
    • https://mzr-avocats.com/buddha/ckfinder/userfiles/files/24300819136.pdfIn PDF document text
    • https://0955205219.jwa.tw/userfiles/files/kasapeganiwidu.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/257e1cd8ecfb66330afabc57dbdf6fa0/4884281821.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/logazuz.pdfIn PDF document text
    • http://posuni.com/userfiles/file/87005348563.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/jaxuzadurejerisafitata.pdfIn PDF document text
    • http://erpsamik.com/ckfinder/userfiles/files/14798630734.pdfIn PDF document text
    • https://geneolock.com/ckfinder/userfiles/files/99381983730.pdfIn PDF document text
    • http://spartapr.com/images/upload/file/70559817501.pdfIn PDF document text
    • http://antasboru.com/guvennet/resimlerfiles/naperojoremekix.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/181658865bfda5527769004889515abc/99539369582.pdfIn PDF document text
    • http://someteme.com/archivos/_20210915215855.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/366e78990398418b533df013cb379679/51046592642.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612ef0fe1b447---gusakinevumivemedizamilu.pdfIn PDF document text
    • http://language-coach.pl/uploads/files/jariwi.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/09-07-00-56-09-66.pdfIn PDF document text
    • http://speckrepeg.by/UserFiles/files/wipij.pdfIn PDF document text
    • https://www.suep.gr/ckfinder/userfiles/files/1214417137.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_off0000b607.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB607 10880 bytes
SHA-256: db0653dfed1515bd8f8ecb84f583799125f7fa8b43bc447e13972d045da1c188
font_01_sfnt_off0000cf5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e770.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE770 15556 bytes
SHA-256: df18f391a42cf14e2afd7b7ccbfef3a81a19fc1ec12c7ade6d3f2e428517003c