Malicious PDF — malware analysis report

Static analysis result for SHA-256 999811813e13d2b2…

MALICIOUS

PDF

68.4 KB Created: 2021-09-28 05:25:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 5c780b137efbbdcc82dd9eb0da7a3341 SHA-1: 674118b592983c3c34790cafd0276f4edeed9725 SHA-256: 999811813e13d2b22904b3fd8da84c1b0875a1ca0b8a96b065461d7e3e47c0f9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://wastran.ru/uplcv?utm_term=instal+ubuntu+on+chromebook PDF link annotation
    • http://zwickerfoto.hu/_user/file/85379507088.pdfIn PDF document text
    • http://boletin.alicantehosteleria.com/lib/ckfinder/userfiles/files/tulemure.pdfIn PDF document text
    • http://www.florentmaussion.net/userfiles/File/lifazako.pdfIn PDF document text
    • https://simbhaolipower.com/images/file/89069240650.pdfIn PDF document text
    • http://tayles.com/uploaded/7420872620.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/60511169359.pdfIn PDF document text
    • http://quimis.net/js/ckfinder/userfiles/files/33310700191.pdfIn PDF document text
    • http://lexprikson.com/admin/style/images/userfiles/file/dizinup.pdfIn PDF document text
    • http://www.pzkexie.com/up_files/file/10322636468.pdfIn PDF document text
    • http://zapatosperezcabrera.com/ckfinder/userfiles/files/gamurovuku.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/d9554a33f20712d3add6a316d350bd70/58678716171.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/d0cfce4d6114b978a7ec0d45ab78e69d/67833163786.pdfIn PDF document text
    • https://braindevelopmentmaps-org.neurondevelopment.org/userfiles/files/nobatinesipuluzog.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/50629045575.pdfIn PDF document text
    • http://jujucuisine.com/userfiles/file/pofalakijekowujusivibo.pdfIn PDF document text
    • http://bbmpva.nl/fckassets/file/7109665545.pdfIn PDF document text
    • http://stauarchitetti.eu/userfiles/files/9878446525.pdfIn PDF document text
    • https://accu-split.com/userfiles/files/35689979349.pdfIn PDF document text
    • https://htlexpress.com/ckfinder/userfiles/files/29300297859.pdfIn PDF document text
    • http://standartbio.com/fckfiles/file/vuvekejapu.pdfIn PDF document text
    • http://pantryscan.com/123cars/imagefck/file/93312436365.pdfIn PDF document text
    • http://pointerboards.com/uploads/admin/files/naxenuze.pdfIn PDF document text
    • https://weilaimachinery.com/userfiles/files/winaze.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613f461792c50---31761793465.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_off0000ae95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE95 10684 bytes
SHA-256: 61adae5fe1fbfcca946e72f2fe5ee7550e0261cfd8213f17d5d3763ef554e4c1
font_01_sfnt_off0000c6f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000df0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF0A 14860 bytes
SHA-256: 36f6bc87e975964330e36ecff5e193e537d82dac63907e808e366bcb792629ba