Malicious PDF — malware analysis report

Static analysis result for SHA-256 b88d188bd0948d62…

MALICIOUS

PDF

116.2 KB Created: 2021-09-03 03:27:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0d005ed9e046c60def07ff0373c63ed8 SHA-1: b9c71c74c77e7090066e5f4816f59be3683e8734 SHA-256: b88d188bd0948d6201eee43e03521eeaf6594bd1bc19fe87600d10333e6caea9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to potentially compromised WordPress upload directories, suggesting a link farm or phishing lure. The presence of a 'download button' heuristic further supports the idea that the document is designed to trick users into downloading a malicious file. ClamAV detection as 'Pdf.Phishing.Trojan' confirms the malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://weberstellen.ch/userfiles/file/fuzafekazimururibotek.pdf In PDF document text
    • http://krasneclanky.cz/uploads/damakufuvejun.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/13617361443.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160c54315c9ae1---jijaxevapalusulubeku.pdfIn PDF document text
    • http://fszhenjia.com/upfolder/e/files/20210613213523.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b5bb244d506---sazerojifav.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/2oph7d9it66v3qkq70l8befp4d/59055699094.pdfIn PDF document text
    • http://toeicspeaking.net/_UploadFile/Images/file/23176754370.pdfIn PDF document text
    • http://salon-urody-bellis.pl/images/file/10047558722.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/lkg4pccvnba0r6ii5s8k3sd3in/67504333646.pdfIn PDF document text
    • https://nhabe.com.vn/ckfinder/userfiles/files/77481375703.pdfIn PDF document text
    • http://elrey-uslugi.ru/media/file/84177394761.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/fofebanimamutudi.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9dc02f1cf3---bagefujoxosimobo.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f84acb394---23616948210.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/202505d4821bd3335b92425530b60446/xixirefogofuxipituz.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab7f8bbf825---naguxuvixefix.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/6ikgf2ota362ffg83pr3n8up2m/wowegisirikofobirikajonov.pdfIn PDF document text
    • http://otohyundaidanang.com/uploads/image/files/bixeviwoj.pdfIn PDF document text
    • http://yotlist.com/uniformkontakt/userfiles/image/files/jukemofowaxixuguboxexit.pdfIn PDF document text
    • http://enslev-anlaegsservice.dk/userfiles/file/bunelutexadotumodobodun.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099707759414---dusojonoragatasefujesimu.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/bf417d8982196007efb600fd85de9702/11366165073.pdfIn PDF document text
    • http://scro.ru/pic/file/biwulananulesuvesesejak.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cca0886611---pawulejadotobimitapato.pdfIn PDF document text
    • http://cesarrodarte.com/userfiles/file/51680200226.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=forensic+report+template+pdfPDF 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_off00015ed9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15ED9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000176f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x176F0 10756 bytes
SHA-256: c4afcbfcea00d5912917821e1aa43b08a78c1213f18a670eeeb8bb16d924ced1
font_02_sfnt_off00018fa6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18FA6 20224 bytes
SHA-256: 790cebea6e740d2cba8932c0e85a0b6f7190a270e49cbb415b5a04931e1ad38c