Malicious PDF — malware analysis report

Static analysis result for SHA-256 7553d77c2ae6ba35…

MALICIOUS

PDF

84.8 KB Created: 2021-09-12 07:48:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b98a69c3ef954134eb66f5703ffcb9a2 SHA-1: 5ff4668e52d9bfc14ae542669c41ddb56598740e SHA-256: 7553d77c2ae6ba358e3069650183e4f90cef4c878dfbc91ed89d96c0a8275584
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be disposable or compromised, suggesting a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a common phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://coretry.ru/uplcv?utm_term=how+to+change+alarm+on+android PDF link annotation
    • http://elsekmont.eu/userfiles/file/79073867404.pdfIn PDF document text
    • http://zzfcw.com/file/fkimg/file/wiwabadifamanugek.pdfIn PDF document text
    • http://www.radeton-cz.vasestranky.cz/ckfinder/userfiles/files/timegeselaluxatom.pdfIn PDF document text
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/75930481982.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138fbc322a72---19701882637.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/setogimupinajepukewe.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/86302928015.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/09/08/file/kukone.pdfIn PDF document text
    • http://aivieksteslaivas.lv/userfiles/file/fedizun.pdfIn PDF document text
    • http://odessawa.com/userfiles/file/16101348105.pdfIn PDF document text
    • http://fohow77.ru/upload/file/31988220755.pdfIn PDF document text
    • http://mail.teleserviciomalaga.com/ckfinder/userfiles/files/gariwulidogemelegidipesu.pdfIn PDF document text
    • http://devison-matras.com/upload/file/60850414116.pdfIn PDF document text
    • http://joyear.com/ckfinder/userfiles/files/57755670012.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/vamukixajanefilamixa.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/238fae77e8868f6cbb38e9c6bf5ed491/gokavuwamusewawoti.pdfIn PDF document text
    • http://labsshop.com/d/files/zamowefejitidux.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/gudetosej.pdfIn PDF document text
    • https://tinhhoaxanh.vn/userfiles/file/19222561913.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/zolepajobux.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/egab549mkburnlu6h6jsg9be94/xixuzemuderefejidikewugi.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_off0000e4d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D7 10724 bytes
SHA-256: f132333ae0d639dd129e0bf432618d313d3ab8ec97fff866e67e6598ef2fb417
font_01_sfnt_off0000fd0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0D 18544 bytes
SHA-256: f4f59e77ad6c9882efde538593fc60aa643d21ba98e12574bfc6a3f13969b404
font_02_sfnt_off00012da5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1