Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb78bb141f6c5f59…

MALICIOUS

PDF

116.6 KB Created: 2021-07-15 12:51:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 58703c797d8cb3954e600bcb30828e13 SHA-1: c597713d8de1c300cf8b345dda43269422f5fb69 SHA-256: fb78bb141f6c5f595c4ba72d163df8e1310efbcb1ce9c31aabeb6a2b19fe53e1
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF functions as a link farm, pointing to numerous URLs hosted on compromised CMS upload storage and disposable hosting. This suggests the document is designed to redirect users to potentially malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://kitapkapla.com/upload/ckfinder/files/jiwutedenetija.pdf In PDF document text
    • http://asja-doll.ru/userfiles/file/92830887962.pdfIn PDF document text
    • http://pappteam.hu/userfiles/file/lijegisabudititidakojuzu.pdfIn PDF document text
    • http://vyveva.eu/UserFiles/File/kafoxotokorapizekono.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608789163ab33---30821216877.pdfIn PDF document text
    • https://birudongker.com/contents//files/xugomerixulal.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606c843096b8b---19132712003.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/9199007208.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/271db7adf71db54d519c29faebada6ec/gezixudijaxixiz.pdfIn PDF document text
    • http://tandprotheses.com/ckfinder/userfiles/files/vusupigajaso.pdfIn PDF document text
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/bewedo.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/5d490e2ef722ccb8b76ec4697ed30964/seselujigupemobik.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da6f5321889---48543261651.pdfIn PDF document text
    • http://dogoducthien.com/uploads/files/donebimo.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/zinolemetej.pdfIn PDF document text
    • http://architettoangeli.it/userfiles/files/jefef.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160ee5c2678073---jugarukeremudiniku.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607f110a6691d---mewud.pdfIn PDF document text
    • https://www.alarisusallc.com/wp-content/plugins/super-forms/uploads/php/files/deef1523f324afe9ec5d290f5f21fb15/90904600888.pdfIn PDF document text
    • http://worldcar.jp/userfiles/files/jodekozasapixojoxuz.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160855d1b0d47a---pelukizojolapugikabovezok.pdfIn PDF document text
    • http://www.vnos.vn/app/webroot/uploads/files/61220054474.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4f9c964e21---litazovita.pdfIn PDF document text
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cc063949c41---kufosozitanevudori.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=what+is+the+collective+noun+for+footballersPDF 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_off000160e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x160E4 20232 bytes
SHA-256: f1c4c770f9c68e0faa18dfd8495d4b6e8df570e42f74745e9f1d195ab0bae743
font_01_sfnt_off00019460.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19460 10732 bytes
SHA-256: e0f5dadbeed190897ddef97b0b08d30f8e699ba411fe413664d6fe33cfbbc2a6
font_02_sfnt_off0001ad07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AD07 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1