Malicious PDF — malware analysis report

Static analysis result for SHA-256 fcba850b3cd5ef68…

MALICIOUS

PDF

94.0 KB Created: 2021-08-01 03:52:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 16ca511433a2cb389239a6fa6052aeaf SHA-1: e053ce6a612ac15d01476a18209868420423e9d7 SHA-256: fcba850b3cd5ef68c81403d932b6a986084ac2e8eb409cf2d63eaa069ac6616a
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous heuristics point to the PDF acting as a link farm, directing users to various external URLs, some hosted on compromised WordPress sites or disposable domains. The presence of embedded URLs and the nature of the heuristics suggest the PDF is used to redirect users, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://garglob.ru/uplcv?utm_term=250+most+common+english+words+and+1000+most+common+english+phrases+pdf PDF link annotation
    • http://hongshengfish.com/uploadfiles/20210602/210602123820643710jvblzgoy1mgf.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/0t8hs80i65bd0opv774cbtdmql/86486175789.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/8f366296d77f6eb60fb85b0c02bda880/jelofabekinener.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/ce80ce266f47de5e157a54d55431a497/mobikojefutodalenefab.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/2205c2ab36a3ab971822a44ab1423a07/19298172791.pdfIn PDF document text
    • http://ort168.com/upload//ckeditor/files/sereb.pdfIn PDF document text
    • http://157.230.241.115/image/upload/File/nagadanonesevobor.pdfPDF link annotation
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f8c96f721e9---musipufakadadob.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/160d19d9f1fe1b---35530345311.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/file/zafuzezigu.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/b0ltuk6g5g2le62m8rinjuldh0/vivirozugagogevefali.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/59830581278.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/1630936d2fe64cfa3aa2b39f2675591f/49619740587.pdfIn PDF document text
    • http://st03.it/userfiles/files/4257425597.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160737bc221b11---49311116289.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f5d1604484---ratanexapaj.pdfIn PDF document text
    • http://cn-daomeng.com/upload/userfiles/files/70083cdda7e0a40da5c1add0d794bf7e.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/39k224mp6voaqr3cmv3t35isl4/xepobofoge.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a2c80bda069---86384195866.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cbe39261020---81494121329.pdfIn PDF document text
    • http://akbarestate.com/survey/userfiles/files/josudinaxusatebi.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_off00010ac2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000122d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122D9 11484 bytes
SHA-256: 0530d2ea716876cc2142c96965479f4d3ecdcfc9c6b4d23333e41a03ebe6ec0c
font_02_sfnt_off00013db9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DB9 17108 bytes
SHA-256: f898b0dd405c4d604d7de195299daef6c190dc740e0bbab3decc4f06883644af