Malicious PDF — malware analysis report

Static analysis result for SHA-256 b549dcd3fc72ae92…

MALICIOUS

PDF

89.2 KB Created: 2021-09-05 22:24:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 28b3ef757dd250401b0b4314abedd390 SHA-1: be42346fa7afca88a27e631f98880ff84ac03dc3 SHA-256: b549dcd3fc72ae92064763f146baa7ced2552ba853a6b4229a505353d9fb0788
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites utilizing the 'super-forms' plugin. These URLs act as a link farm, redirecting to other domains, suggesting an attempt to obscure the final malicious destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://oniceh.ru/uplcv?utm_term=french+cuisine+recipe+book+pdf PDF link annotation
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/792a931ca135cf26b8044b9386628754/85174982643.pdfIn PDF document text
    • http://nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/pexemujajawasila.pdfIn PDF document text
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/e362975c465dc6a9db2936efdb83fd91/41622532161.pdfIn PDF document text
    • http://xaydunglenguyen.vn/upload/files/3565f7.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/59458935634.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/b96db9b2c3a2f2c139f234ed8a8d52ca/safavabexuzijuzedon.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea3f077512---duvojezudosalogu.pdfIn PDF document text
    • http://spoanalyze.com/wp-content/plugins/super-forms/uploads/php/files/739684dddb3613b0ec85130ce0e5d208/disosixulunovevusima.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2cc0cb1816---wifugejixipikujuparoj.pdfIn PDF document text
    • https://haltia.mx/sii/ckfinder/userfiles/files/11539268824.pdfIn PDF document text
    • http://rogalafamilyreunion.org/clients/0/0d/0db8e8e54aa701f14f52e26b989c21c2/File/87175849631.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160794a3836a4f---305277030.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/eclnam1dtu48kc98dq57psg3u2/14854254703.pdfIn PDF document text
    • http://transbur.ru/admin/ckfinder/userfiles/files/93440555515.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad3f636ad3---fixusenuka.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609675aeefb41---zezinopi.pdfIn PDF document text
    • http://kasaitogo.com/uploads/files/somogazizafuzepudegoji.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073eca8a4056---razawero.pdfIn PDF document text
    • http://voxel-avocats.fr/uploads/file/besovipixetebisuxa.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/160ada810e374e---12021882259.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/892979d39d3e89513a646a2a0c6d5606/terazanejopa.pdfIn PDF document text
    • http://www.cenlajobinator.com/siteuploads/editorimg/file/58598389191.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/6bc9f23be8b4865b7c3f9527f8fc3e22/mubevanebijifatasiwina.pdfIn PDF document text
    • https://pilot-nav.com/ckfinder/userfiles/files/saviwenaravogofimi.pdfIn PDF document text
    • 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_off0000f508.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF508 19328 bytes
SHA-256: 6754f380df20790880dcaeeee4b0810bc006c6fb9f38acd27d6a4ea23a9413d9
font_01_sfnt_off0001268b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1268B 10720 bytes
SHA-256: ae68fd79a2f1d94f242bedcd704d9065a3d15b1062fa8259b9c575854355e793
font_02_sfnt_off00013ec4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1