Malicious PDF — malware analysis report

Static analysis result for SHA-256 d819bc70df426cc2…

MALICIOUS

PDF

99.3 KB Created: 2021-09-21 04:23:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1d3541ae5f3e80fb24c86d66befe5d96 SHA-1: 7da6d28d86c9c205d5cb4d32bc079397444909f2 SHA-256: d819bc70df426cc22ad4887e5fa009e799a59eb9f795188b0fe87f09797f49b9
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as containing a link farm pointing to compromised CMS uploads and disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically a phishing trojan. The document body is heavily obfuscated and unreadable, but the presence of numerous external URIs suggests an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://hotelgiottotorino.com/userfiles/files/12731703042.pdf
    • https://matao.ro/app/webroot/files/userfiles/files/28064451936.pdf
    • http://sanitaerprofi.ch/fckeditor/editor/images/file/12728066367.pdf
    • http://files.ibiza-ferien.de/file/54302840452.pdf
    • http://vnos.vn/app/webroot/uploads/files/44655238825.pdf
    • http://studioambienteterritorio.it/userfiles/files/43700563012.pdf
    • http://rentator.com/uploades/fckeditorfile/kixekubejobiwisowem.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a0b79db68e---15123229733.pdf
    • http://www.espace-hotelier.com/ckfinder/userfiles/files/56808477468.pdf
    • http://zbraneklapka.cz/ckfinder/userfiles/files/80750284536.pdf
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/ee31c9ec2ee8214cf2b9ad07cffe9415/fadek.pdf
    • http://www.eau-msu.ru/ckfinder/userfiles/files/xukenamolik.pdf
    • http://maslatalaia.com/userfiles/file/92972479291.pdf
    • https://lawina-radom.pl/files/file/ziwozol.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bdb256561e---84376508578.pdf
    • http://phaptangpgvn.net/app/webroot/upload/files/35608579296.pdf
    • http://traiteur-ribot.fr/userfiles/file/24854308973.pdf
    • https://0a3exp.com/upfiles/editor/files/pamotawitifakeramujak.pdf
    • http://sendedianqi.com/upload_fck/file/2021-9-18/20210918210615939586.pdf
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/857f5b146f9efa2bd95796e0edd8ecde/93980134000.pdf
    • http://peter-scherer.de/userfiles/file/24894507210.pdf
    • http://stylekd.ru/files/63986728983.pdf
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/161433facd74e5---32111420655.pdf
    • http://epmresearch.org/userfiles/files/kumujipotefurexugerotem.pdf
    • http://apicn.net/upload/files/vewiserubuxuden.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=free+notes+for+android
    • 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_off00011fad.bin
b18bdea5f219459dda1aacbed06f1491a99aa4f7879c248dc9ff589e513ca157
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FAD 18920 bytes
font_01_sfnt_off00015043.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15043 16792 bytes
font_02_sfnt_off0001685a.bin
be818697cb5593c8200ba11375d35b8e977d9458f8a1877b5079a47e472a42c4
pdf-font-stream PDF embedded font (sfnt) at offset 0x1685A 10276 bytes