Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fd8b710925ce8e4…

MALICIOUS

PDF

78.3 KB Created: 2021-09-17 16:20:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a74ba003222cec1ebd2bc7cbd2eec884 SHA-1: fcacf35c09aafb7ff415e7a82293f872e06e4c1a SHA-256: 4fd8b710925ce8e4b78e3053c73de0633e7aa32f1b00aff9a71307dbf9cfbc18
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on disposable or compromised domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • 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.
  • 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://oniceh.ru/uplcv?utm_term=skyrim+gauldur+amulet+puzzle
    • http://autosklo.sk/pictures/file/35849226220.pdf
    • http://annassteen.com/ckfinder/userfiles/files/15428092681.pdf
    • http://almawred-sy.com/files/adminfiles/files/wenosolavefatebajab.pdf
    • http://feminella.ro/upload/fck/nenewotoditifurib.pdf
    • https://adetexfoamgroup.centralcms.cloud/galeria/files/22566824980.pdf
    • http://ahzycw.com/upload_fck/file/2021-9-7/20210907022323439620.pdf
    • https://louvre.lv/res/wysiwyg/file/18851522465.pdf
    • https://kidneystonetreatment.in/userfiles/files/pizamimem.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142f8a26b870.pdf
    • http://j1medical.com/uploaded/file/lifezivuxowiwepudigenifa.pdf
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/93613826000.pdf
    • http://kyochonbuenapark.iorderfoods.com/uploads/files/nosoxotekiwapujubupu.pdf
    • http://ranahytta.com/ckfinder/userfiles/files/wajudat.pdf
    • http://igabana.com/upfolder/e/files/20210909054438.pdf
    • http://downtowncincyhotels.com/core_degree/admin/images/cms_imagesfiles/pemopeteged.pdf
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b6d77de838---vikevetidejowosaninojonuv.pdf
    • http://carneiro-sa.pnh.pt/js/ckfinder/userfiles/files/tumabapa.pdf
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff745ddf30---13301777763.pdf
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/89023758681.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135bfbe8135c---repixavuwizur.pdf
    • https://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/pozodok.pdf
    • https://www.cascatai.com.br/ckfinder/userfiles/files/xavipevejotimejop.pdf
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613a22645e8fb---vewebixurikolopite.pdf
    • http://khocabien.com/uploads/files/bululidiwafefoxusofanat.pdf
    • http://vicc.huh.hu/UserFiles/File/fajufigebeno.pdf
    • http://chanakol.com/ckfinder/userfiles/files/peladeg.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_off0000ca39.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA39 16792 bytes
font_01_sfnt_off0000e250.bin
8530cb8a63a2bbf3a9c16f3b0743f734205df75cd1b41643b9d8a468e1aa5d20
pdf-font-stream PDF embedded font (sfnt) at offset 0xE250 10784 bytes
font_02_sfnt_off0000fb01.bin
101060307edb108848247b59c41a3e1a52541c16300d578f6cbfabf719449af5
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB01 18608 bytes