Malicious PDF — malware analysis report

Static analysis result for SHA-256 a49becd5566522f1…

MALICIOUS

PDF

82.5 KB Created: 2021-09-03 07:15:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 48753302b946cdc7b375b2467be27eae SHA-1: ae988ea98062c79d0666d3f5b6395f1f3be56652 SHA-256: a49becd5566522f1132cc2399da7131df39c2023a7259ae68c727b8e5350e255
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress upload directories and other disposable hosting. These links likely lead to further malicious content, such as phishing pages or additional malware payloads. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user interaction but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3e4493ee1---20916286120.pdf In PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160a605d68f386---20221175383.pdfIn PDF document text
    • http://apcmagon.com/userfiles/39529531124.pdfIn PDF document text
    • https://performanceltg.com/wp-content/plugins/super-forms/uploads/php/files/04a9ebff39917c2f36a7d73e124b2153/76499122725.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607b7db1db136---68529067489.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/nalagabebatumulile.pdfIn PDF document text
    • http://dichvutheapec.com/upload/FCK/file/35125795130.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/672edc36d6deeca647839213601f8d30/xatunekirutedatonubepaker.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/c486de6e36b202b957f474fabe2dac72/migorovibejawunupoma.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16096d9e66ba54---ropizekobumeloz.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160720a7c0c157---kisokabozuxaxedo.pdfIn PDF document text
    • https://shiokerbau1.com/contents//files/30841483068.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16070377ac0cf1---warebid.pdfIn PDF document text
    • http://kasand.com/userfiles/gorezomutujepoti.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/7ifrrfsbul3ukgemd2jr48i0nr/dajufesetasunefe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=uml+openclassroom+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_off0000d8ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8EF 19448 bytes
SHA-256: 7c13870610eb7ac0ace1ef191561e27f75894e7303bc20dcdabd62000c3ce554
font_01_sfnt_off00010b79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B79 10596 bytes
SHA-256: 04e282e8ca59e700b3b0277e8c92a373728c04eb5ff9dd117fc2b6887f413a97
font_02_sfnt_off000123a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1