Malicious PDF — malware analysis report

Static analysis result for SHA-256 581c4819d12eddd0…

MALICIOUS

PDF

87.3 KB Created: 2021-06-20 07:43:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: f12177ea281cf6ee59b6124aa7c56567 SHA-1: 937f03899f6a18b477926b6e20eae98639d0fc04 SHA-256: 581c4819d12eddd0340346e5e987bd106912b6e953d511019d41fc566eb9bef5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a common PDF-based lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9052

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://medvor.ru/uplcv?utm_term=granny+por+pic PDF link annotation
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/fcd92346a36bab5dc42247c53b815ec0/xelamivegubemadixux.pdfIn PDF document text
    • https://bandai-k.com/userfiles/file/56972486985.pdfIn PDF document text
    • http://yuha.be/_files/file/67523396953.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607936d959db3---masozodosamotubok.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160bd224a60e93---59670974940.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/vilusizafanit.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/6292b1026a18a9a24f0ea6e50726071d/46855631180.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/7ehqsld1ssuld4j47r5ulkrgs6/tugebaguwesiwumu.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b86e59038---64541666620.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/3f1c1b999782d66d1841436c9c796f5e/72272947915.pdfIn PDF document text
    • http://famillespourstarlight.ca/clients/a/a9/a9b42c05011d3bb27e7f7ec2ed30324f/File/bafagelod.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160a62cca9d0e7---tanixidimaxutewijo.pdfIn PDF document text
    • http://lhs60to70.com/clients/3/32/32806278e47d7e4d905c37b1d6ebf04a/File/wovere.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/f23c20c17f1d5efdf920e8e28df92f80/58686654992.pdfIn PDF document text
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/2502a42e6aa3dd250cbce9934462543b/dimijizizakomifisemofela.pdfIn PDF document text
    • https://aradmissions.com/ci/userfiles/files/95874813270.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/21415316552.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001000e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1000E 4848 bytes
SHA-256: 52f18bec336e001d066ef81d696ba38d01d0ccf80107249ad4bda0b5a8f0f80f
font_01_sfnt_off000110a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A2 3272 bytes
SHA-256: 544363b59adcde79cef456d5c7a1f8053e4aba958e1bd541ee20a2a2b6c39c03
font_02_sfnt_off00011e39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E39 12128 bytes
SHA-256: 4475bb0b44304458dc7280272811e2279317b05db99b69f8fd4adf6340c3660f
font_03_sfnt_off00014617.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14617 16168 bytes
SHA-256: 794d8cc090a449e0d460036171b2d5b2c749cb0dc3f17972c44626ada68ee3d8