Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3e3eeff81dc7651…

MALICIOUS

PDF

85.1 KB Created: 2021-09-12 11:27:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1b163d5e1797ad35a91193677f79f42a SHA-1: 98d0ee43907ecd410b8b693a5279e39aba97f517 SHA-256: f3e3eeff81dc765103929819a8a562897badf1ddc1de18e6883c1c051cd6b8bd
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress sites and disposable hosting, suggesting an attempt to distribute further malicious content or phish users. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b116abaf15---xozekurodedokabusin.pdf In PDF document text
    • http://www.pibmg.com.br/ckfinder/userfiles/files/files/2921938925.pdfIn PDF document text
    • https://ahha.az/userfiles/file/38810045623.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613af6cf94b74---34247949650.pdfIn PDF document text
    • http://montesantangelo.it/files/files/vifuro.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/dokoxajogifefopanafosit.pdfIn PDF document text
    • http://changjiujz.com/uploads/files/202109021457123723.pdfIn PDF document text
    • https://indiachristian.org/uploads/files/sigof.pdfIn PDF document text
    • http://fitviewer.com/files/file/88837886248.pdfIn PDF document text
    • https://ptkas.com/kingkong/userfiles/files/90672511441.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/90123792932.pdfIn PDF document text
    • http://0225674989.kad.tw/kads/ckfinder/userfiles/files/4663023254.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/276f2a7674237e2fd9b2dcb73ffc3f07/89670725206.pdfIn PDF document text
    • http://bolt-go77.com/fckeditor/userfiles/file/40617648382.pdfIn PDF document text
    • http://caratow.eu/userfiles/file/4273776721.pdfIn PDF document text
    • http://interstyle.org/content/xuploadimages/file/21838887575.pdfIn PDF document text
    • http://artwatch.ru/userfiles/file/mapedipovabimimezuxapeba.pdfIn PDF document text
    • https://mimpishio1bet.net/contents/files/vedefemaketok.pdfIn PDF document text
    • http://thietbikhachsanvinhhung1.com/upload/files/47142284868.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613585e867a10---42960074243.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161398311692d3---divejima.pdfIn PDF document text
    • https://matfreklam.com/calisma2/files/uploads/60205977553.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/4527272094.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16135f1429a832---64304278173.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=extrem+car+driving+hackPDF 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_off0000e7c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ffd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD8 18140 bytes
SHA-256: 3fb03d3de13d60b85a34f8efde6463e3308d1009660f8cff1d92df14c86c7a82
font_02_sfnt_off00012e8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E8D 10724 bytes
SHA-256: b6e15954c057cd0fd871414f110d5b8197652905e71c9d78c04a159f578e2f84