Malicious PDF — malware analysis report

Static analysis result for SHA-256 608b1fc9a5d1f116…

MALICIOUS

PDF

81.6 KB Created: 2021-09-07 20:17:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e54be3abcb356337cc564d95f92579d7 SHA-1: bb086c53ca3cbbb7f18106c6df8fdbb6feb330ba SHA-256: 608b1fc9a5d1f116a7980bf87953e445c633082e21749828d06a91390c07112e
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites and disposable hosting, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing sites or download further malware. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://bogelaipigeon.com/upload/file/77549937275.pdf In PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/c9b4b3b710a41e7387005843459b70cd/67880590976.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081be3482716---34808781293.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/nowajumikul.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/3r6uom985q1ep9vndrk1klc4t7/wewir.pdfIn PDF document text
    • http://congseng.com/uploadfile/files/69932328266.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/xifiwezabijewepu.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/40940708566.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d178aecb49---kefevo.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608409155735f---silib.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607afbecd3b74---lajininisuzozas.pdfIn PDF document text
    • http://hamlineparkplaza.com/assets/amund/ckfinder/userfiles/files/62682158748.pdfIn PDF document text
    • http://edwardlankin.com/clients/86087/File/48331952550.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/6c1cda80df0d51ed3930c3cbe53371a1/kusijeveso.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/465lkf70scfdgq1r26888rrid3/5881483522.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/80219999574.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160e2c17174cff---wosilisivevabawek.pdfIn PDF document text
    • http://labonguyenhoang.com/img-chamthi/files/fapezosat.pdfIn PDF document text
    • https://drddvichitra.com/userfiles/file/6951474605.pdfIn PDF document text
    • https://www.corpeverest.com/ckfinder/userfiles/files/89499479783.pdfIn PDF document text
    • http://safeabortionnepal.com/userfiles/file/bidajaxelejikuzigukobud.pdfIn PDF document text
    • http://www.szphotar.com/admin/img/files/rusimexafabefokiwegugun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=change+default+pdf+viewer+xiaomiPDF 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_off0000d8fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f110.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF110 17696 bytes
SHA-256: f36f88b363872782876dc716753f620e05bf31a18bd2be6e9f9a83eaba66bc54
font_02_sfnt_off00011f19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F19 11160 bytes
SHA-256: 0b8d5eb715e62ab443278c615663acf00628966b4f253c4b4a8426d2e92ee5b4