Malicious PDF — malware analysis report

Static analysis result for SHA-256 50e37556c4576a4f…

MALICIOUS

PDF

80.0 KB Created: 2021-07-03 19:51:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: a0b742958b3a2079586c38ed885ccb1d SHA-1: 69a95dbd0c02fcb4377442d6e8296c7667bbdd61 SHA-256: 50e37556c4576a4f6485a3a2dcfa7aec2485211d778b438aee89b4ee859b3094
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress upload directories and other disposable hosting sites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV also flagged this file as malicious, suggesting it is used to distribute further malicious content or lead users to phishing sites. The embedded URLs are likely part of a campaign to lure victims to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://pokemom2.com/uploads/files/kolipegufurexadoguxaje.pdf In PDF document text
    • http://irinaburmistrova.ru/files/51739025544.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/3a433731e7d48547308241e20850d438/vazujanew.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9efe0873a7---8754550876.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/59530960156.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/067fc777f23ed0a8dc2b5f1bb8e30b79/ruzoxetu.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/072d6c52393fddd8c20701d26f95be30/jekel.pdfIn PDF document text
    • http://sport-way.ru/img/file/zenuxuzu.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c1e5df9abbc---35800007521.pdfIn PDF document text
    • https://comtraining.cl/userfiles/files/babubeguganomolosetunobe.pdfIn PDF document text
    • http://sshs61.com/clients/6/60/60e739d5a8cf4a6710e4f064fd99417d/File/78632538695.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/1831551455f110ec7cdfd43adb0922a1/16339282207.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/vodiwa.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/zusorifezaf.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d188d878657---durimib.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160844cb764caf---91386189229.pdfIn PDF document text
    • http://klccpa.com/userfiles/file/nawaxu.pdfIn PDF document text
    • http://nsfeed.com/_UploadFile/Images/file/76918693580.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a09a8692416---memopitorejizabor.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/sewosivadut.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/gubizigu.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608b764505b85---vobotegamugirixok.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16091d2bfd0f6b---86968182158.pdfIn PDF document text
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/18de6fee35936c1af2825b8f35adeea2/27051272838.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=exponent+properties+with+productsPDF 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_off0000d5eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5EB 16848 bytes
SHA-256: 7ec9fcec942be25dd8914dbc1ec0de837009d73145f4899b2fc49f833754fc99
font_01_sfnt_off0001020c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1020C 10672 bytes
SHA-256: c2105d66a450c21547eef1b160b487b50ecb2c4e720483fa453f47fd77dd1eac
font_02_sfnt_off00011a88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1