Malicious PDF — malware analysis report

Static analysis result for SHA-256 8af5e4a50b02767a…

MALICIOUS

PDF

91.1 KB Created: 2021-08-11 19:02:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0e6c51b36a55c3eb038fa436e5f91766 SHA-1: 53d1aa476898e6e042efbc96793fd6791c422525 SHA-256: 8af5e4a50b02767a58cbf9c172de16bd0b8c3194f90aa8da3eec581f240f9a7b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised websites and other PDF files, indicating a link farm designed to redirect users. Heuristics suggest this is a phishing or malware distribution attempt, with ClamAV specifically identifying it as a 'Pdf.Phishing.Trojan'. The ML classifier also strongly flagged the PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://pistant.ru/uplcv?utm_term=l%C3%ADmites+de+funciones+de+varias+variables+definici%C3%B3n
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/a0467d9abfd3e2a4da99dfbbbf991697/masofajodugerul.pdf
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/bdfeedf9c009d74f7fb9f53a81b5d54f/95580303819.pdf
    • https://vpntraffic.com/upload/files/soreturewo.pdf
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/6fjivrvdqt5d2j5b0vancalb5s/kazojumupozobobixililu.pdf
    • https://dietacud.eu/upload/file/69819898232.pdf
    • http://fongyoskert.hu/userfiles/files/911086203.pdf
    • http://change4best.ru/upload/file/dixibon.pdf
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609305cc524c5---76250957989.pdf
    • http://eyela.kr/uploadfile/fckeditor/file/xubukazexiruruxel.pdf
    • http://liyangah.com/Upload/file/92874320158.pdf
    • https://marcuspietrek.de/MARCUS/files/file/65282026224.pdf
    • http://dichvutot99.com/webroot/img/files/gorapedewujisak.pdf
    • http://insidethedigitaltrend.biz/userfiles/file/69424798483.pdf
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c87dc1ff54---tubalojojurekemewamazaba.pdf
    • https://theatresaucinema.fr/uploads/file/64054671671.pdf
    • http://wedding-ideas.ru/ckfinder/userfiles/files/wevegadogivuxurewazu.pdf
    • http://chongthamnguoc.vn/img/files/13880854426.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5bd8c03a01---91348941795.pdf
    • http://kaitosushisb.com/uploads/files/18874937519.pdf
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0d0069997---29297197199.pdf
    • http://accomplishtheimpossible.com/userfiles_ati/file/97347094421.pdf
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160837d891db8e---12482296534.pdf
    • http://springgalleryng.com/Images_upload/files/12349498823.pdf
    • https://radmangroup-ye.com/rgfiles/file/kubaja.pdf
    • http://radtel-sport.pl/userfiles/file/nutuzogosotofafotode.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_off0000f74e.bin
870043096cdb1281ec3aa2205684d88cecbc38f00fdf9420f6edf949369e021d
pdf-font-stream PDF embedded font (sfnt) at offset 0xF74E 11100 bytes
font_01_sfnt_off000110e4.bin
0195853ddadcf3953833e5e03ecfacef9c2a2f6ad3fad40161e962b744ef5576
pdf-font-stream PDF embedded font (sfnt) at offset 0x110E4 19276 bytes
font_02_sfnt_off000142d9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x142D9 16792 bytes