Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c819f3ec8b277e6…

MALICIOUS

PDF

83.3 KB Created: 2021-09-22 18:55:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d595a59d7011ca0e6fa906db92abda6e SHA-1: 642a7edcec0ccd9422d52a73401cadbf0c6a016a SHA-256: 7c819f3ec8b277e609ee0dfb4ba6d34f77b30802b6026d44defd44b69200cefd
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 identified as part of a link farm hosted on potentially compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://synerhu.ru/uplcv?utm_term=imovie+mod+apk+for+android PDF link annotation
    • https://el-tall.pl/pics/file/63188496375.pdfIn PDF document text
    • http://jd6618.com/jd6618/file/2021-9/file/LwpCms2021_09_05_11_19_09_8915.pdfIn PDF document text
    • https://krygina40.ru/UserFiles/File/42627733843.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/161403c1da7b59---pominasuzobanedet.pdfIn PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/25335478780.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/39124319988.pdfIn PDF document text
    • http://cachnhietwin.com/luutru/files/91459298319.pdfIn PDF document text
    • http://www.peretprod.ro/content-images/file/89828906695.pdfIn PDF document text
    • http://mstreatmentadvances.com/userfiles/files/pipesozusetagelorezofina.pdfIn PDF document text
    • http://sichera.eu/userfiles/files/41155302114.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/9b40ebb78b10974ddb878c067f477075/56785875488.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bb9ed9b56d---suzofifuzudisixisogomuju.pdfIn PDF document text
    • http://harasim.cz/uploaded/files/61774356291.pdfIn PDF document text
    • https://pemaboutiquehotel.com/assets/userfiles/files/80278067126.pdfIn PDF document text
    • https://menuiserie-sainte-anne.fr/userfiles/file/tuvapiwudoriju.pdfIn PDF document text
    • http://jatechkj.pl/upload/fck/file/rilosegizawodal.pdfIn PDF document text
    • http://indyztyle.com/ckfinder/userfiles/files/nukalolexa.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/42038765815.pdfIn PDF document text
    • https://dianthusindustrial.com/resimler/files/xexumofipomawu.pdfIn PDF document text
    • http://mmbassisiprovince.in/files/js/ckfinder/userfiles/files/fakarikivininosesagamuf.pdfIn PDF document text
    • http://fijiembajak.com/uploads/ck_uploads/files/58985069795.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_off0000e0fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0FC 10456 bytes
SHA-256: af43507c8b822bd46ead5aa017a1ec40450487a8cd5bee7b26282481e1b66d5d
font_01_sfnt_off0000f8a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A7 17864 bytes
SHA-256: 97d209fb5f40741c66a30d99d7ceb6b41d76f642020c02c409b2fc6516c771c8
font_02_sfnt_off00012746.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12746 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1