Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb9b4b84682d54e0…

MALICIOUS

PDF

79.8 KB Created: 2021-06-29 10:18:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b68e445c32766088aa850e8cd7d19586 SHA-1: 99ff5b9e1eacfb5faf6362ab4ed571d4e73102dc SHA-256: fb9b4b84682d54e071fc5f66e42d34b4bc1efcc51b9fe6e300f713ab2f967476
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, with external URIs like https://inwebjor.ru/uplcv?utm_term=grindr+xtra+free+hack. The document body is heavily obfuscated, preventing analysis of its direct content, but the overall structure and URL analysis strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://inwebjor.ru/uplcv?utm_term=grindr+xtra+free+hack PDF link annotation
    • http://thecobbfr.com/clients/4/43/4363d5a08aa72aedcf7f7d4dd0675897/File/72999888747.pdfIn PDF document text
    • http://bestbuyfromindia.com/userfiles/file/71470155675.pdfIn PDF document text
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/514ee33acecb92d936c023f5a7765f8e/51895161585.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/c8c28acf0a8178925ecce403cd99f9a4/kapijazamububag.pdfIn PDF document text
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/5695efa80d6fb3b315350530ccc018e0/rabusuno.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c1fb60b8cb7---vawefewulobovipitiziw.pdfIn PDF document text
    • http://au-zlato.sk/upload/files/27548632094.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/c4f6322e39c3d8f7f604bc2ee5b91983/zawemelimulebudibas.pdfIn PDF document text
    • http://divorce-difficile.fr/userfiles/file/98764133304.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b3d1f0446a7---4368676381.pdfIn PDF document text
    • https://99shayari.in/userfiles/files/lufilolimeged.pdfIn PDF document text
    • http://roocenter.ru/upload/file/juganijezolabitugonagireb.pdfIn PDF document text
    • https://www.varishastalari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5d9456e63---tebalegepagonaluv.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/78603581663.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/20445275783.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/dq86gmctme27hqieikjeo3cqp5/dizodaxebozopafifefo.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/ef6c6ea21036f0ffbef5c093655c4a94/56358042424.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/4e26732d5319ab91a43aa40d1839dde0/nipuwututelimezowanix.pdfIn PDF document text
    • http://chromatographvials.com/d/files/97148561010.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608731db2fa34---61243142118.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/abeij271fg8oe8mnqsi3pbnatk/62483229218.pdfIn PDF document text
    • https://daiichitravel.com/uploads/news_file/22288831523.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/9776j4gvgmp4go9u42i3t9vtpo/wilukedufofat.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/tijusewikoxijisel.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d60cbb49bd0.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_off0000d33b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD33B 17356 bytes
SHA-256: 6b0f62b28ca205cac604628547455ff0c89cb0160230e45d71ead81b8481be90
font_01_sfnt_off000100d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000118e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118E7 10472 bytes
SHA-256: da2fbc217be3bb5bd06c8adf68b126cd9981d4cb74fc8155323b6b4e60bd996b