Malicious PDF — malware analysis report

Static analysis result for SHA-256 877bd0c46ce2e9f6…

MALICIOUS

PDF

84.3 KB Created: 2021-07-31 00:50:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 56c2658c8a1b835f76a6d2f57600b61d SHA-1: 3e4f1f94653d2f19632b0dc451d911d1ed99135b SHA-256: 877bd0c46ce2e9f604e8a1212f260bd9e9777e9738106e18eb7bf3809ae72a09
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple compromised WordPress sites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded URLs are likely used to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a866a3a7e56---31447805879.pdf In PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/f43b5c738b871913fdc7d6cfa4191b48/somerizi.pdfIn PDF document text
    • http://atek-ent.com/upload/file/napibe.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/nuwefobonipulo.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1aed4600f2---65113513177.pdfIn PDF document text
    • http://zetrade.cz/userfiles/file/55937153216.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/87591342464.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/fgrong8avdnhth3f6khf3p72dk/gatiwedifabunoj.pdfIn PDF document text
    • https://gaziemirkentkonseyi.com/upload/files/risesiw.pdfIn PDF document text
    • https://bompentax.com/quangbasanpham/app/webroot/upload/image/files/2869592532.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c895284a957---fudifubujalawupevad.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160aa1e30642d8---35782907994.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d842289d29---fuwaputavos.pdfIn PDF document text
    • https://hoalavender.net/upload/files/12075877062.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/rjmqtn7767bcm8bnngffhg7iun/73894704113.pdfIn PDF document text
    • http://anhopphat.com/uploads/files/43418348065.pdfIn PDF document text
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/e6318363682e96b0cc9131cfdb1125b0/kuxonupuzedosubitujumo.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/46df6b68fda6dea8c8b0c05ed01f97bb/65104178427.pdfIn PDF document text
    • http://kibbkw.com/uploads/file/wofosepoxazakivupoterew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=herramientas+manuales+de+construccion+pdfPDF 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_off0000e59b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE59B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fdb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDB2 10872 bytes
SHA-256: 5c35d117f4739a3a3b0bb67ae49922edbcf57fbcd25f049f9ec68b36741e29f4
font_02_sfnt_off000116b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116B9 17588 bytes
SHA-256: 2ee2578f976f5d1bb2f2695c74793da0a2837dd2354b184c7a12b4d22abd7550