Malicious PDF — malware analysis report

Static analysis result for SHA-256 7651a8d8ecf92766…

MALICIOUS

PDF

85.1 KB Created: 2021-06-26 10:25:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f1f2ee4e37552f2670eb10c39e5eeeb6 SHA-1: 5a57bb5f35e30384729e0ee02548567217a712c8 SHA-256: 7651a8d8ecf927660892194b1501520d249ab108bc6ee760c36c6e3bd35e001d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It contains a large number of embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a non-clustered link farm on disposable hosting, further supporting the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://infrive.ru/uplcv?utm_term=computer+graphics+and+multimedia+mcq+with+answers PDF link annotation
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/55567310848.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/faxes.pdfIn PDF document text
    • https://maggies-handmade.com/UserFiles/files/gokewe.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/52339b362459d05dfff77346b373fc1a/wefadekiti.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/rifulito.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607603ed69a13---38815065807.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/09rojvaq65ma65ag9d8h92q5m2/sajeto.pdfIn PDF document text
    • http://extracam.es/app/webroot/arxius/file/62655661064.pdfIn PDF document text
    • http://vodnik48.ru/content/file/beguzibanil.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/ba49a1d70aa531faec2dcc79c14a76f9/sugunen.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cbaf99118d---94799738009.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/ee3cf48449c08ba00a7201cf956671f6/2813232933.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/9vd6v93f2jmi5m76d86khh1v63/55936762091.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/dibakafifewe.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/678d5d21284c22d1329e2d61d9c03056/13095569143.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/f6seb6c36kukam63gijing5p95/9995615215.pdfIn PDF document text
    • http://fbchitchcock.org/clients/8/8b/8bdff38a390027835eb24981312b950c/File/gofumozumedowa.pdfIn PDF document text
    • http://wmehoa.org/clients/d/df/dff1b85474dadb967ea0c40f6d5e37f8/File/kikimobobazutevefabavil.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/12055224644.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/13561608365.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/4ab053790695e3bcce84548664beb011/73877466946.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608a0fb219e36---vawavefuvuv.pdfIn PDF document text
    • https://cupanghitam.com/contents//files/34596683415.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a89fe6bf451---5373738918.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_off0000e58e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fda0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDA0 17372 bytes
SHA-256: d7e9c76fb2d7365eccac4b2e72b85017b17eb6fe61d3479e05ba0872d7f56ad1
font_02_sfnt_off00012b05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B05 11324 bytes
SHA-256: 7a35895c398851f46973aad8a37e242ae79ea7cf68d0098bc80e254f1415d97a