Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e8b887d61809cb3…

MALICIOUS

PDF

85.4 KB Created: 2021-07-19 09:20:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: f40a1a5374e861d46870c24e5d1e438a SHA-1: aa631942757d6f1de85482c04669649a74a7a152 SHA-256: 9e8b887d61809cb35058952f793a33d4d0e5f65ff338e864ae26f6421e20c757
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm with numerous URLs, many pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware sites. The document body is unreadable, but the heuristic findings and URL analysis are sufficient to determine its malicious nature as a link distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/14f36d96081a156e687c2d9a6982005b/zunivudakasapugiwuteni.pdf In PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16084ecb5c092e---kimolofizo.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/54057a19350366964f08d48bf2ce4e7a/75970900498.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/d44deb1bf81c0d726bef05386bb7358d/86634596701.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/lvnl2qo1cci3jbf6gcajdaod06/xexifetom.pdfIn PDF document text
    • https://tecnicadovolante.com/images/file/vulumigedexolokatuku.pdfIn PDF document text
    • https://guineaservicesproviders.com/gsp/files/41739672378.pdfIn PDF document text
    • http://rc-modeller.se/images/file///fuwevokumanuf.pdfIn PDF document text
    • https://thaiwoodengames.com/files/upload/files/12354520212.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f11318b872---73079125168.pdfIn PDF document text
    • https://ceral.pl/ceral/pliki/file/lidodubovusixugi.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/ca5cb5effb3aac9c3094645fda72da91/kamanidonum.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a3969837bc7---galeniba.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/9e67050be01d82ba21417a997096e1d2/69112928042.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/p5h22f7li2b53cjotmv6bk9hnh/82294113413.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/2peg925moirhvt71e4e1tleqr6/guxibaramizigusikagutogu.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/kowamugemaw.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160a819fad77c1---96205504718.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/46835092749.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/vikvijubsn1c1g7p4ve8qemig2/ragen.pdfIn PDF document text
    • http://studioaba.net/userfiles/files/lokojuzotod.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/25566041312.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160874d189410f---sosenapufokufuv.pdfIn PDF document text
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e2f8db8ccb---zodefe.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160d067a0b6bd2---nojasadorojikor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=when+someone+says+thank+you+how+do+you+respondPDF 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_off0000e82e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE82E 17292 bytes
SHA-256: cfc45b2a830d8289214bee530e60415693353c1cea4dda9b3ff5c44efbb5c18a
font_01_sfnt_off000114ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012ce5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CE5 10904 bytes
SHA-256: 907e50151b2008af60c28da9f6c3e863abd86c660d9b8bcb1e48f006b2d72023