Malicious PDF — malware analysis report

Static analysis result for SHA-256 c99564a35378a84e…

MALICIOUS

PDF

79.7 KB Created: 2021-07-16 04:22:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4131dbf6198b534b730d08d698f8c8f3 SHA-1: 8a9c7f1de0ac9dcdf00f510c89c87513ed49e5e8 SHA-256: c99564a35378a84e9d810c4dae7675867bdc2832801203619f57d2d06eaa0103
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://queure.ru/uplcv?utm_term=cda+family+questionnaire+summary+sheet+examples
    • http://perilatomsk.ru/ckfinder/userfiles/files/30467502779.pdf
    • https://autoteam.in/ckfinder/userfiles/files/zazaroroviterijomo.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/hmrpfo3g046m8igg3p5s57ar42/7914856264.pdf
    • http://phongkhamthienhoa.org/images/files/vurutebidibobotudo.pdf
    • https://glearningsolutions.com/userfiles/files/13617718908.pdf
    • http://dolinakrzeptowa.pl/public/upload/ckfinder//userfiles/files/fumavekem.pdf
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/2e690f61b46a9b7d36b008c66e50488f/siborakafumawanotobada.pdf
    • https://bursac.net/userfiles/file/bosomodolokap.pdf
    • https://censcakmu.org/board/file/files/mupajowo.pdf
    • http://www.grupoaccs.net/ckfinder/userfiles/files/40599737687.pdf
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/62f9fd47a12950d7ea8cd791f290af54/48119242166.pdf
    • http://intergeored.com/upload/File/31237426785.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/841fdefff6d28b753d18f456b174c881/fagadimovomomenuk.pdf
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607567cf27b01---fegesajuzodiwegifi.pdf
    • https://aterhesseg.com/up_image/file/98448825303.pdf
    • https://www.litesourcenc.com/wp-content/plugins/super-forms/uploads/php/files/3975f9109b0fc9d9b3847c2e71aa4642/rivofasenogefo.pdf
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c92436da5f---50691527056.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a10c23e1796---24514127852.pdf
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/4abfc406c1b8047eba89e9ad4c64fa8c/59836173265.pdf
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7affdd9eb1a9c11ad8243c0cb02aca8e/gawepavuviw.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ad0e6f2c740---zotulanidodado.pdf
    • http://alliance-ltd.com/userfiles/57446830918.pdf
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/qm4lvckc7eqlakjhb881b06jhn/49183247913.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d38f.bin
0bc32ec3792054c7112f7a4a8ecdab04db5dd3402d8e87eb309e1b0a407371e3
pdf-font-stream PDF embedded font (sfnt) at offset 0xD38F 11256 bytes
font_01_sfnt_off0000ed97.bin
84d0a16c29815f8cffce5ce3ea57dbe937582abf80cd02fe5edb79964f77575f
pdf-font-stream PDF embedded font (sfnt) at offset 0xED97 16784 bytes
font_02_sfnt_off0001195e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1195E 16792 bytes