Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a51906c1e4d6c58…

MALICIOUS

PDF

76.2 KB Created: 2021-09-18 19:49:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3303dd1878cfc8e11de01e034ff634e6 SHA-1: f9b229d0ab7b9a0b704c283456d07a01843bc038 SHA-256: 5a51906c1e4d6c58a93051b85ac18a161a562e1da8ff04116a530b61c7d79a75
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier with high confidence. It contains numerous links to external domains, many of which are hosted on compromised WordPress sites or disposable hosting, suggesting a link farm or phishing lure. The presence of embedded URLs and the overall structure indicate an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://infrive.ru/uplcv?utm_term=itunes+preparing+iphone+for+restore+stuck PDF link annotation
    • http://babyshelter.net/assets/upload/files/37558622366.pdfIn PDF document text
    • http://pushgroup.lv/userfiles/files/35891285971.pdfIn PDF document text
    • https://mimpishio2bet.com/contents/files/3433559173.pdfIn PDF document text
    • http://intertravel.hu/_user/file/diweweka.pdfIn PDF document text
    • http://caratow.nl/userfiles/file/99731695804.pdfIn PDF document text
    • https://szelvedojavitasmiskolc.hu/files/files/47909144030.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16137dbea4ed5d---60190748844.pdfIn PDF document text
    • http://sangsangins.com/upload/upload/file/zumeparitenokepegogijor.pdfIn PDF document text
    • https://anfauglir.com/images/file/mezuketisa.pdfIn PDF document text
    • http://geosond.pl/userfiles/file/gibapurosirekipinimigizen.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f976a7788a---711045397.pdfIn PDF document text
    • http://tao-oita.com/admin/upload_filesfile/56797456785.pdfIn PDF document text
    • http://ginzaramen.us/uploads/files/dutebuj.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/pewovagepazebup.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/09/202109080002482676.pdfIn PDF document text
    • http://honeycontacts.com/uploades/userfiles/file/4282330879.pdfIn PDF document text
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/97951212961.pdfIn PDF document text
    • https://aucordechasse.fr/vosImages/78851243436.pdfIn PDF document text
    • http://www.radio-kum.si/data/files/39108134707.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/jogulojixitegetar.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/f2vbuerbgpdo06a3eanibucqie/10674513425.pdfIn PDF document text
    • https://commonlawhouse.in/userfiles/file/ladanuzozusarojirugosozi.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161321ccdd8e6d---watavux.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_off0000c49a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC49A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dcac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCAC 17556 bytes
SHA-256: a67d93da3c0c2e96f5f409087eb33e7e0f1bb54f38001040c42d8f9994e1c764
font_02_sfnt_off000109f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109F5 10856 bytes
SHA-256: 1507e533202df709fb85b2f7de6cfb2d5c032645d33e74c41dad3a4b80db46c2